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151. The role of hyperconjugative π-aromaticity in the enhanced acidity of methyl-, silyl and germylcyclopentadienes

Author: Alberto González-Castrillo, Otilia Mó, Marcela Hurtado, Manuel Yáñez, and Jean-Claude Guillemin
Subjects: Cyclopentadiene, Silylation, Biophysics, Substituent, Aromaticity, Condensed Matter Physics, Ring (chemistry), Photochemistry, Medicinal chemistry, chemistry.chemical_compound, Deprotonation, Cyclopentadienyl complex, chemistry, Physical and Theoretical Chemistry, Molecular Biology, Methylcyclopentadiene
Abstract: The relative stability of the different isomers of cyclopentadienyl derivatives CpXH3 (X = C, Si, Ge) and their intrinsic acidities have been investigated by means of B3LYP/6-311+G(3df,2p)//CCSD/6-311+G(d,p) density functional theory calculations. Whereas for the methylcyclopentadiene the 1- and 2- substituted isomers are almost equally stable and much more stable than the 5-substituted isomer, for the germyl derivatives the 5-substituted compound is the global minimum, due to the stabilization of the system through a hyperconjugative π-aromaticity effect, which is the larger the more electropositive the XH3 substituent is. As a consequence CpXH3 (X = Si, Ge) are more aromatic than cyclopentadiene. The silyl and germyl derivatives are more fluxional than the methyl derivative, the 1,2-XH3 shift activation barriers being around 60 kJ mol−1. For all the isomers, the most favourable deprotonation process corresponds to the loss of the proton attached to the sp3 carbon atom of the five membered ring. For Si a...
Published: 2010
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152. Microwave and Quantum Chemical Study of Propargyl Thiocyanate (HC≡CCH2SC≡N)

Author: Rajmund Mokso, Harald Møllendal, and Jean-Claude Guillemin
Subjects: Work (thermodynamics), Thiocyanate, 010405 organic chemistry, Dihedral angle, 010402 general chemistry, 01 natural sciences, Spectral line, 0104 chemical sciences, chemistry.chemical_compound, Crystallography, chemistry, Computational chemistry, Excited state, Alkane stereochemistry, Propargyl, Physical and Theoretical Chemistry, Conformational isomerism
Abstract: The MW spectrum of propargyl thiocyanate (HC≡CCH 2 SC≡N) has been investigated for the first time in the 25-80 GHz spectral region at room temperature or at 0 °C. The spectra of the ground vibrational state and of the first excited state of the C-S torsional vibration have been assigned for one conformer. This rotamer, denoted ap, has a symmetry plane (C, symmetry) and an antiperiplanar arrangement for the C-C-S-C link of atoms. It has previously been claimed that a conformer that has a synclinal conformation for this chain of atoms is present in the gas in approximately the same concentration as ap (∼50% of the gas), but this is not supported by the present experiments, where it is shown that the synclinal rotamer, denoted sc, cannot be present in a concentration exceeding 1/3 of the total. It is therefore concluded that ap must be al least 3.0 kJ/mol more stable than sc. The spectroscopic work has been augmented by quantum chemical calculations at advanced B3LYP/aug-cc-pVQZ, B3LYP/6-31 1++G(3df,3pd), and MP2/aug-cc-pVTZ levels of theory. These theoretical calculations underestimate the energy difference between ap and sc and predict values for the conformationally important C—C—S—C dihedral angle of the hypothetical synclinal form that deviates by ∼10°.
Published: 2010
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153. Synthesis and Microwave Spectrum of (2-Chloroethyl)phosphine (ClCH2CH2PH2)

Author: Alexey Konovalov, Jean-Claude Guillemin, and Harald Møllendal
Subjects: chemistry.chemical_compound, Torsional vibration, Computational chemistry, Chemistry, Excited state, Alkane stereochemistry, Physical chemistry, Rotational spectroscopy, Physical and Theoretical Chemistry, Conformational isomerism, Microwave, Phosphine, Spectral line
Abstract: The synthesis of a 2-halogenoethylphosphine, (2-chloroethyl)phosphine (ClCH(2)CH(2)PH(2)), is reported for the first time. This compound was prepared by a chemoselective reduction of diethylchloroethylphosphonate with dichloroalane using a vacuum line. (2-Chloroethyl)phosphine has been studied by microwave spectroscopy at room temperature, or at -20 degrees C, in the 22-80 GHz spectral interval. The experimental study has been augmented by quantum chemical calculations at the MP2/6-311++(3df,3pd) and B3LYP/6-311++(3df,3pd) levels of theory. The spectra of two rotameric forms, denoted I and II have been assigned. These conformers both have an antiperiplanar arrangement for the Cl-C-C-P chain of atoms, but with different orientation of the phosphine group. Conformer I was found to be 5.2(6) kJ/mol more stable than II by relative intensity measurements. The spectra of the first excited states of the C-C torsional vibration of both I and II were assigned. The torsional frequency was determined to be 63(20) cm(-1) for conformer I by relative intensity measurements, and it has a similar value in II. It was found that this normal vibration deviates from a near-harmonic behavior. The quantum chemical calculations produce rotational and centrifugal distortion constants that are in satisfactory agreement with observations, but fail to predict correctly low-frequency fundamental frequencies. The quantum chemical calculations indicate that three additional conformers characterized by a synclinal orientation for the Cl-C-C-P link of atoms and with different orientation of the phosphine group are high-energy forms of ClCH(2)CH(2)PH(2). Searches for these forms were unsuccessful.
Published: 2009
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154. Gas-Phase Infrared Spectra of Vinyl Selenol and Vinyl Tellurol

Author: Brahim Khater, Abdessamad Benidar, Jean-Claude Guillemin, Manuel Yáñez, José A. Gámez, Astrochimie expérimentale, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Synthèses et activations de biomolécules (SAB), Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Centre National de la Recherche Scientifique (CNRS), Departemento de Química C-9, Universidad Autónoma de Madrid (UAM), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR), and Universidad Autonoma de Madrid (UAM)
Subjects: Vinyl alcohol, Vinyl Compounds, Vapor pressure, Infrared spectroscopy, 010402 general chemistry, Photochemistry, Vibration, 01 natural sciences, chemistry.chemical_compound, Coordination Complexes, Organoselenium Compounds, Spectroscopy, Fourier Transform Infrared, 0103 physical sciences, [CHIM]Chemical Sciences, Computer Simulation, Physical and Theoretical Chemistry, 010306 general physics, Conformational isomerism, Basis set, Selenol, Hydrogen atom, 0104 chemical sciences, Models, Chemical, chemistry, Quantum Theory, Physical chemistry, Density functional theory, Gases
Abstract: International audience; The infrared spectra (3500-500 cm(-1)) of gaseous vinyl selenol and vinyl tellurol have been recorded at 0.1 cm(-1) resolution. For the latter the spectra were obtained at room temperature, but for the former a temperature of -40 degrees C was required because of the chemical instability of vinyl selenol at room temperature. To compensate the very weak vapor pressure of vinyl tellurol at room temperature, a long optical path up to 136 m was necessary to record its spectrum. B3LYP density functional theory (DFT) calculations have been performed to assign the different absorption bands. Since an unambiguous assignment of the absorption bands requires a precise knowledge on the relative abundance of the syn and gauche rotamers of these compounds, their relative energies and their anharmonic vibrational frequencies were obtained using a very extended Def2-QZVP basis set. Two rotamers, the syn, which is planar, and a nonplanar gauche, were found to be local minima for both compounds. The gauche rotamer presents two degenerate conformers, which differ by the position of the SeH (TeH) hydrogen atom above or below the molecular plane. Our theoretical results are in good agreement with the main features of the experimental spectra. Fundamental bands and some combination bands of vinyl selenol and vinyl tellurol were assigned and compared with those of vinyl alcohol and vinyl thiol, whose spectra had been reported previously in the literature.
Published: 2009
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155. Primary Phosphines Studied by Gas-Phase Electron Diffraction and Quantum Chemical Calculations. Are They Different from Amines?

Author: Sarah L. Masters, David W. H. Rankin, Brahim Khater, Robert Noble-Eddy, Heather E. Robertson, Derek A. Wann, and Jean-Claude Guillemin
Subjects: Models, Molecular, Molecular Structure, Phosphines, Ab initio, Electrons, Inorganic Chemistry, chemistry.chemical_compound, Crystallography, Molecular geometry, Models, Chemical, chemistry, Electron diffraction, Computational chemistry, Ab initio quantum chemistry methods, Propargyl, Quantum Theory, Molecule, Computer Simulation, Gases, Amines, Physical and Theoretical Chemistry, Conformational isomerism, Phosphine
Abstract: The molecular structures of allyl-, allenyl-, propargyl-, vinyl-, ethynyl-, phenyl-, benzyl-, and chloromethyl-phosphine have been determined from gas-phase electron diffraction data employing the SARACEN method. The experimental geometric parameters are compared with those obtained using ab initio calculations performed at the MP2 level using both Pople-type basis sets and the correlation-consistent basis sets of Dunning. The structure and conformational behavior of each molecule have been analyzed and, where possible, comparisons made to the analogous amine. For systems with multiple conformers, differences in the CCP bond angle of approximately 5 degrees between conformers are common. Trends in the key parameters are identified and compared with those found in similar systems.
Published: 2009
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156. Microwave Spectrum and Intramolecular Hydrogen Bonding of 2-Propene-1-selenol (H2C═CHCH2SeH)

Author: Harald Møllendal, Alexey Konovalov, and Jean-Claude Guillemin
Subjects: chemistry.chemical_classification, Double bond, 010405 organic chemistry, Chemistry, Hydrogen bond, Selenol, Hydrogen atom, 010402 general chemistry, Photochemistry, 01 natural sciences, Spectral line, 0104 chemical sciences, Crystallography, chemistry.chemical_compound, Intramolecular force, Molecule, Physical and Theoretical Chemistry, Conformational isomerism
Abstract: The microwave spectrum of 2-propene-1-selenol, H(2)C=CHCH(2)SeH, has been investigated in the 45-80 GHz spectral range at -30 degrees C. The spectra of six isotopologues of one conformer, which has an anticlinal orientation for the C=C-C-Se chain of atoms and a synclinal conformation for the C-C-Se-H link, were assigned. This conformational preference allows for the formation of an intramolecular hydrogen bond between the hydrogen atom of the selenol group and the pi electrons of the double bond. This hydrogen-bonded conformer is at least 3 kJ/mol more stable than any further rotameric form of the molecule. The microwave study has been augmented by quantum chemical calculations at the MP2/6-311++G(3df,3pd) and B3LYP/6-311++G(3df,3pd) levels of theory. These calculations indicate that additional rotamers have higher energies, by approximately 3-12 kJ/mol, than the identified conformer. The conformational properties and internal hydrogen bonding of H(2)C=CHCH(2)SeH is compared with their counterparts of the corresponding alcohol and thiol.
Published: 2009
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157. Synthesis, Microwave Spectrum, and Conformational Equilibrium of Propa-1,2-dienethiol (H2C═C═CHSH)

Author: Jean-Claude Guillemin, Brahim Khater, and Harald Møllendal
Subjects: Quantum chemical, 010405 organic chemistry, Chemistry, Spectrum (functional analysis), Dihedral angle, 010402 general chemistry, 01 natural sciences, Spectral line, 0104 chemical sciences, 3. Good health, Crystallography, Computational chemistry, Theoretical methods, Physical and Theoretical Chemistry, Conformational isomerism, Microwave
Abstract: The first synthesis of the kinetically unstable compound propa-1,2-dienethiol (allenethiol; H(2)CCCHSH) is reported. Its microwave spectrum has been studied in the 41.5-80 GHz spectral range. The spectra of two rotameric forms have been assigned. The C-C-S-H chain of atoms is synperiplanar (0 degrees ) in one of the conformers. This dihedral angle is anticlinal in the second rotamer forming an angle of 140(5) degrees in the second form. The synperiplanar conformer is found to be 1.0(6) kJ/mol more stable than the anticlinal rotamer. The microwave study has been augmented by quantum chemical calculations at the MP2/aug-cc-pVTZ and B3LYP/6-311++G** levels of theory. The predictions of these two theoretical methods are in excellent agreement with the experimental findings.
Published: 2009
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158. Microwave and Quantum Chemical Study of Propargyl Selenocyanate (HC≡CCH2SeC≡N)

Author: Jean-Claude Guillemin, Harald Møllendal, and Alexey Konovalov
Subjects: chemistry.chemical_compound, Crystallography, Thiocyanate, chemistry, Excited state, Propargyl, Alkane stereochemistry, Physical and Theoretical Chemistry, Dihedral angle, Triple bond, Conformational isomerism, Spectral line
Abstract: The MW spectrum of propargyl thiocyanate (HC[triple bond]CCH(2)SC[triple bond]N) has been investigated for the first time in the 25-80 GHz spectral region at room temperature or at 0 degrees C. The spectra of the ground vibrational state and of the first excited state of the C-S torsional vibration have been assigned for one conformer. This rotamer, denoted ap, has a symmetry plane (C(s) symmetry) and an antiperiplanar arrangement for the C-C-S-C link of atoms. It has previously been claimed that a conformer that has a synclinal conformation for this chain of atoms is present in the gas in approximately the same concentration as ap (approximately 50% of the gas), but this is not supported by the present experiments, where it is shown that the synclinal rotamer, denoted sc, cannot be present in a concentration exceeding 1/3 of the total. It is therefore concluded that ap must be at least 3.0 kJ/mol more stable than sc. The spectroscopic work has been augmented by quantum chemical calculations at advanced B3LYP/aug-cc-pVQZ, B3LYP/6-311++G(3df,3pd), and MP2/aug-cc-pVTZ levels of theory. These theoretical calculations underestimate the energy difference between ap and sc and predict values for the conformationally important C-C-S-C dihedral angle of the hypothetical synclinal form that deviates by approximately 10 degrees.
Published: 2009
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159. α,β-Unsaturated and Saturated Derivatives of Be, Mg, and Ca: Are They Carbon or Metal Acids in the Gas Phase?

Author: Ane Eizaguirre, Manuel Yáñez, Jean-Claude Guillemin, Otilia Mó, Departemento de Química C-9, Universidad Autónoma de Madrid (UAM), Departamente de Quimica, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Autonoma de Madrid (UAM), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Alkaline earth metal, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Hydride, Organic Chemistry, Heteroatom, Inorganic chemistry, General Chemistry, 010402 general chemistry, 01 natural sciences, Medicinal chemistry, Bond-dissociation energy, Catalysis, Dissociation (chemistry), 0104 chemical sciences, 3. Good health, Metal, Deprotonation, Chemical bond, visual_art, visual_art.visual_art_medium, ComputingMilieux_MISCELLANEOUS
Abstract: The gas-phase acidity of R--XH (R=H, CH(3), CH(2)CH(3), CH==CH(2), C[triple chemical bond]CH; X=Be, Mg, Ca) alkaline-earth-metal derivatives has been investigated through the use of high-level CCSD(T) calculations by using a 6-311+G(3df,2p) basis set. BeH(2) is a stronger acid than BH(3) and CH(4) for two concomitant reasons: 1) the dissociation energy of the Be--H bond is smaller than the dissociation energies of the B--H and C--H bonds, and 2) the electron affinity of BeH(.) is larger in absolute value than those of BH(2) (.) and CH(3) (.). The acidity also increases on going from BeH(2) to MgH(2) due to these two same factors. Quite importantly, despite the fact that the X--H bonds in the R--XH (X=Mg, Ca) derivatives exhibit the expected X(delta+)--H(delta-) polarity, they behave as metal acids in the gas phase and only Be derivatives behave as carbon acids in the gas phase. The ethylberyllium hydride exhibits an unexpected high acidity compared with the methyl derivative because deprotonation of the system is accompanied by a cyclization that stabilizes the anion. Similarly to that found for derivatives that contain heteroatoms from groups 14, 15, and 16, the unsaturated compounds are stronger acids than the saturated counterparts, with the only exception of the Ca-vinyl derivative. Most importantly, among ethyl, vinyl, and ethynyl derivatives containing a heteroatom of the main group of the Periodic Table, those containing Be, Mg, and Ca are among the strongest gas-phase acids.
Published: 2008
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160. A Quantum Chemical Study of the Generation of a Potential Prebiotic Compound, Cyanoacetaldehyde, and Related Sulfur Containing Species

Author: Anne Horn, Jean-Claude Guillemin, Harald Møllendal, Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Pyrimidine, Hydrogen sulfide, Protonation, Acetaldehyde, Activation energy, 010402 general chemistry, 01 natural sciences, 7. Clean energy, chemistry.chemical_compound, Computational chemistry, Ab initio quantum chemistry methods, 0103 physical sciences, Cyanoacetylene, Molecule, Computer Simulation, Hydrogen Sulfide, Sulfhydryl Compounds, Physical and Theoretical Chemistry, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Addition reaction, Evolution, Chemical, Molecular Structure, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 0104 chemical sciences, Models, Chemical, chemistry, 13. Climate action, Quantum Theory
Abstract: Cyanoacetaldehyde (NCCH 2CHO), which may have played a role in the prebiotic formation of the pyrimidine bases cytosine and uracil, is formed in water solutions by addition of water to cyanoacetylene (HCC-CN), a compound that exists in interstellar space, in comets, and planetary atmospheres. A gas-phase model of the uncatalyzed addition of water to cyanoacetylene is explored by ab initio calculations at the MP2/6-311++G** level of theory. A reaction path consisting of several steps was found in these calculations, but the activation energy of the first step is relatively high, which makes it unlikely that cyanoacetaldehyde is formed in an uncatalyzed reaction. Similar calculations were also performed for the uncatalyzed reaction of water to protonated cyanoacetylene (HCCCNH (+)), a component of the interstellar medium, forming protonated cyanoacetaldehyde (HNCCH 2CHO (+)), but a high activation energy was found for this reaction as well. Moreover, the corresponding addition reactions of hydrogen sulfide (H 2S) to HCCCN, as well as to HCCCNH (+), have been explored with similar results.
Published: 2008
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161. A Microwave and Quantum Chemical Study of Cyclopropanethiol

Author: Rajmund Mokso, Harald Møllendal, Jean-Claude Guillemin, European Synchrotron Radiation Facility (ESRF), Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: 010304 chemical physics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 0103 physical sciences, Physical and Theoretical Chemistry, 010402 general chemistry, 01 natural sciences, ComputingMilieux_MISCELLANEOUS, 0104 chemical sciences
Abstract: The microwave spectra of cyclopropanethiol, C(3)H(5)SH, and one deuterated species C(3)H(5)SD, have been investigated in the 20 - 80 GHz frequency range. The spectra of the ground vibrational state and of three vibrationally excited states of the parent species of a conformer which has a synclinal ("gauche") arrangement for the H-C-S-H chain of atoms, was assigned. The H-C-S-H dihedral angle is 76(5)° from synperiplanar (0°). The b-type transitions of the ground and of the vibrationally excited states of the parent species were split into two components, which is assumed to arise from tunneling of the proton of the thiol group between two equivalent synclinal potential wells. No splitting was resolved in the spectrum of C(3)H(5)SD. The tunneling frequency of the ground vibrational state of C(3)H(5)SH is 1.664(22) MHz. The tunneling frequency of the first excited-state of the C-S torsion is 52.330(44) MHz, whereas this frequency is 26.43(13) and 3.286(61) MHz, respectively, for the first excited states of the two lowest bending vibrations. The dipole moment of the ground vibrational state of the parent species is μ(a) = 4.09(5), μ(b) = 2.83(11), μ(c) = 0.89(32), and μ(tot) = 5.06(16) × 10(-30) C m. The microwave study has been augmented by high-level density functional and ab initio quantum chemical calculations.
Published: 2008
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162. Functionalized Tellurols: Synthesis, Spectroscopic Characterization by Photoelectron Spectroscopy, and Quantum Chemical Study

Author: Brahim Khater, Gabor Bajor, Jean-Claude Guillemin, Tamás Veszprémi, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics [Budapest] (BME), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Quantum chemical, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Chemistry, Tributyltin hydride, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, 3. Good health, Characterization (materials science), Cyclopropane, Inorganic Chemistry, chemistry.chemical_compound, X-ray photoelectron spectroscopy, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS
Abstract: Ethene-, cyclopropane-, 3-butene-, and cyclopropanemethanetellurol have been synthesized by reaction of tributyltin hydride with the corresponding ditellurides and characterized by 1H, 13C, and 125Te NMR spectroscopy and high-resolution mass spectrometry. The tellurols of this series, with a gradually increasing distance between the tellurium atom and the unsaturated group, have been studied by photoelectron spectroscopy and quantum chemical calculations. Two stable conformations of ethenetellurol and cyclopropanetellurol, five of allyltellurol, and four of cyclopropanemethanetellurol were found. In the photoelectron spectrum of vinyltellurol, the huge split between the first two bands indicates a direct interaction between the tellurium lone electron pair and the double bond. In the allyl derivative, a hyperconjugation effect was found for the most stable conformers. In contrast to the vinyl compounds, no direct interaction between the lone electron pair of X (X = O, S, Se, and Te) and the three-membered ring could be observed in the cyclopropyl derivatives. A hyperconjugation-like effect, which is independent of the relative orientation of the X-H group, is found to increase from S to Te. Thus, the type and extent of the interaction between the TeH group and an unsaturated or cyclopropyl moiety are clarified while the first comparison of interactions between the nonradioactive unsaturated chalcogen derivatives is performed.
Published: 2008
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163. Elusive anion growth in Titan’s atmosphere: low temperature kinetics of the C3N−− + HC3N reaction

Author: Ludovic Biennier, Baptiste Joalland, Muthiah Balaganesh, Sébastien D. Le Picard, Jérémy Bourgalais, Nour Jamal-Eddine, Michael Capron, Jean-Claude Guillemin, Alexandre Faure, Sophie Carles, Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), This research was supported by the French National Research Agency (ANR) through a grant to the Anion Cos Chem project (ANR-14-CE33-0013), the CNRS-INSU Programme National de Physique et Chimie du Milieu Interstellaire and the CNRS-INSU Programme National de Planétologie. We thank Daniel Cordier for his help concerning the kinetics analysis. This work also benefited from discussions with our colleagues Ján Z̆abka, Christian Alcaraz, Claire Romanzin, Véronique Vuitton and Roland Thissen. J.-C. G. thanks the Centre National d’Etudes Spatiales (CNES) for financial support. S. L. P. thanks the Institut Universitaire de France (IUF) for financial support., ANR-14-CE33-0013,Anion Cos Chem,Explorer la Chimie et Spectroscopie des Anions Cosmiques(2014), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Analytical chemistry, Chemistry – Ionospheres, 010402 general chemistry, 01 natural sciences, Spectral line, Ion, Atmosphere, symbols.namesake, Mass transfer, 0103 physical sciences, Elementary reaction, Physique moléculaire, Atmosphere of Titan, 010303 astronomy & astrophysics, [PHYS]Physics [physics], Chemistry, Astronomy and Astrophysics, Atmospheric temperature range, CRESU, 0104 chemical sciences, Atmosphere – Atmospheres, 13. Climate action, Space and Planetary Science, symbols, Atomic physics, Titan (rocket family), Molecular physics, Titan, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; Ion chemistry appears to be deeply involved in the formation of heavy molecules in the upper atmosphere of Titan. These large species form the seeds of the organic aerosols responsible for the opaque haze surrounding the biggest satellite of Saturn. The chemical pathways involving individual anions remain however mostly unknown. The determination of the rates of the elementary reactions with ions and the identification of the products are essential to the progress in our understanding of Titan’s upper atmosphere. We have taken steps in that direction through the investigation of the low temperature reactivity of C3N−,−, which was tentatively identified in the spectra measured by the CAPS-ELS instrument of the Cassini spacecraft during its high altitude flybys. The reaction of this anion with HC3N, one of the most abundant trace organics in the atmosphere, has been studied over the 49–294 K temperature range in uniform supersonic flows using the CRESU technique. The proton transfer is found to be the main exit channel ( > 91%) of the CView the MathML source315N−− + HC3N reaction. It remains however indistinguishable with the non-isotopically labeled CView the MathML source314N−− reactant. The T−1/2T−1/2 temperature dependence of this proton transfer reaction and its global rate are reasonably well reproduced theoretically using an average dipole orientation model. A minor exit channel, reactive detachment ( < 9%), has also been uncovered, although the nature of the neutral products has not been determined. It is concluded that the CView the MathML source314N−− + HC3N reaction cannot contribute to the growth of molecular anions in the upper atmosphere of Titan. Due to the low branching into the neutral exit channel, it cannot contribute either to the growth of neutrals even assuming a complete mass transfer.
Published: 2016
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164. Millimeter wave spectra of carbonyl cyanide

Author: Belén Tercero, Roman A. Motiyenko, Jean-Claude Guillemin, S. B. Bteich, José Cernicharo, Laurent Margulès, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), CNES, Centre National d'Etudes Spatiales, ERC-2013-Syg-610256-NANOCOSMOS, ERC, European Research Council, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Ministerio de Economía y Competitividad (España), Ministerio de Ciencia e Innovación (España), European Research Council, Centre National de la Recherche Scientifique (France), Institut national des sciences de l'Univers (France), and Centre National D'Etudes Spatiales (France)
Subjects: Atoms, 010504 meteorology & atmospheric sciences, Methods: laboratory: molecular, Cyanide, Ground state, Line: identification, laboratory: molecular [Methods], Millimeter waves, Context (language use), Astrophysics, 7. Clean energy, 01 natural sciences, Molecular physics, Article, Spectral line, ISM: abundances, Submillimeter: isms, chemistry.chemical_compound, 0103 physical sciences, [CHIM]Chemical Sciences, identification [Line], Submillimeter: ISM, 010303 astronomy & astrophysics, molecules [ISM], 0105 earth and related environmental sciences, Physics, abundances [ISM], Cyanides, Methods: laboratory, Molecular data, ISM [Submillimeter], Excited states, Astronomy and Astrophysics, Hydrogen atom, Molecules, Quantum number, ISM: abundance, ISM: molecules, Interstellar medium, chemistry, 13. Climate action, Space and Planetary Science, Excited state, Quantum theory
Abstract: [Context] More than 30 cyanide derivatives of simple organic molecules have been detected in the interstellar medium, but only one dicarbonitrile has been found and that very recently. There is still a lack of high-resolution spectroscopic data particularly for dinitriles derivatives. The carbonyl cyanide molecule is a new and interesting candidate for astrophysical detection. It could be formed by the reaction of CO and CN radicals, or by substitution of the hydrogen atom by a cyano group in cyanoformaldehyde, HC(=O)CN, that has already been detected in the interstellar medium., [Aims] The available data on the rotational spectrum of carbonyl cyanide is limited in terms of quantum number values and frequency range, and does not allow accurate extrapolation of the spectrum into the millimeter-wave range. To provide a firm basis for astrophysical detection of carbonyl cyanide we studied its millimeter-wave spectrum., [Methods] The rotational spectrum of carbonyl cyanide was measured in the frequency range 152−308 GHz and analyzed using Watson’s A- and S-reduction Hamiltonians., [Results] The ground and first excited state of v5 vibrational mode were assigned and analyzed. More than 1100 distinct frequency lines of the ground state were fitted to produce an accurate set of rotational and centrifugal distortion constants up to the eighth order. The frequency predictions based on these constants should be accurate enough for astrophysical searches in the frequency range up to 500 GHz and for transition involving energy levels with J ≤ 100 and Ka ≤ 42. Based on the results we searched for interstellar carbonyl cyanide in available observational data without success. Thus, we derived upper limits to its column density in different sources., B.T. and J.C. thank MINECO for funding support from the CONSOLIDER-Ingenio program “ASTROMOL” CSD 2009-00038, AYA2012-32032, CTQ 2013-40717 P, CTQ 2010-19008, and the ERC synergy grant ERC-2013-Syg-610256-NANOCOSMOS. J.-C.G., L.M. and R.M. thank the Centre National d’Etudes Spatiales (CNES) and the Program Physique et Chimie du Milieu Interstellaire (PCMI) (INSU-CNRS) for grants.
Published: 2016
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165. An experimental study of the reactivity of CN- and C3N- anions with cyanoacetylene (HC3N)

Author: Joël Lemaire, Claire Romanzin, Essyllt Louarn, Jean-Claude Guillemin, Christian Alcaraz, Ján Žabka, Miroslav Polášek, Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), J. Heyrovský Institute of Physical Chemistry, Prague, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), This work has been supported by the French National Program of Planetology, the 'Triangle de la Physique' – FCS Campus Paris Saclay under the contract n° 2012-027T-GIN, the COST program Action CM0805 'The Chemical Cosmos: Understanding Chemistry in Astronomical Environments', the COST program Action TD1308 'Origins and Evolution of Life on Earth and in the Universe', the Czech Science Foundation (Grant No. 14-19693S) and the Ministry of Youth and Sports of Czech Republic (Grant No. LD14024).The authors acknowledge their collaborators V. Vuitton, R. Thissen, S. Le Picard, L. Biennier and S. Carles for valuable discussions. C.A. and C.R. thank J.-C. Loison for his help with the calculations. J.-C. G. thanks the Centre National d’Etudes Spatiales (CNES) for financial support., Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Anions, Proton, FTICR-MS, Cyanide, Kinetics, Analytical chemistry, Ionic bonding, 010402 general chemistry, 01 natural sciences, Ion, chemistry.chemical_compound, Reaction rate constant, 0103 physical sciences, Cyanoacetylene, [CHIM]Chemical Sciences, Reactivity (chemistry), Ionosphere, 010303 astronomy & astrophysics, Cyanoacetylide, Reactivity, Astronomy and Astrophysics, 0104 chemical sciences, Chemistry, chemistry, 13. Climate action, Space and Planetary Science, Atomic physics, Experiments, Titan
Abstract: The reactions of the CN − and C 3 N − anions with cyanoacetylene HC 3 N, of special interest for the chemistry of Titan’s upper atmosphere, have been investigated by means of FTICR mass-spectrometry. Primary ions, CN − and C 3 N − , have been produced by dissociative electron attachment (DEA) from BrCN and BrC 3 N, and prepared in a clean way before reaction. Total rate constants have been measured for both reactions at 300 K and are found to be as follows: (3.9 ± 0.5) × 10 −9 and (1.0 ± 0.2) × 10 −10 cm 3 s −1 for the reaction of HC 3 N with CN − and C 3 N − , respectively. For the CN − + HC 3 N reaction, proton transfer is found to be the only reactive channel within our detection limits. Proton transfer is also dominant for the C 3 N − + HC 3 N reaction but the resulting ionic product being identical to the primary ion C 3 N − , this process is transparent for the kinetics of the C 3 N − + HC 3 N reaction and the kinetic rate retrieved corresponds to a slow and competitive detachment pathway. Yet the nature and energetics of the neutral product(s) formed through this process remain unknown. Additional experiments using isotopic products have allowed to retrieve specific rate constants associated with the proton transfer channel in the C 3 15 N − + HC 3 N and C 3 N − + HC 3 15 N reactions and the measured rates are found to be significantly lower than for the CN − + HC 3 N system. This decrease and the evolution of reactivity when going from CN − to C 3 N − and the opening of a new detachment pathway are finally discussed.
Published: 2016
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166. MILLIMETER WAVE SPECTRUM and ASTRONOMICAL SEARCH for VINYL FORMATE

Author: Belén Tercero, Lucie Kolesniková, Carlos Cabezas, José Cernicharo, Elena R. Alonso, JoséL. Alonso, Jean-Claude Guillemin, Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 13-BS05-0008, ANR, Agence Nationale de la Recherche, ERC, European Research Council, 2013-SyG, ERC, H2020 European Research Council, 610256, ERC, H2020 European Research Council, ANR-13-BS05-0008,IMOLABS,Molecules interstellaires : spectroscopie et synthèse en laboratoire(2013), European Research Council, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia e Innovación (España), Junta de Castilla y León, Centre National de la Recherche Scientifique (France), Centre National D'Etudes Spatiales (France), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Techniques: spectroscopic, 01 natural sciences, 7. Clean energy, Ethyl formate, Spectral line, spectroscopic [Techniques], chemistry.chemical_compound, 0103 physical sciences, Molecule, [CHIM]Chemical Sciences, Formate, 010303 astronomy & astrophysics, Conformational isomerism, molecules [ISM], Physics, 010304 chemical physics, Molecular data, Molecular cloud, Astronomy and Astrophysics, Catalogues, ISM: molecules, Interstellar medium, chemistry, Space and Planetary Science, Excited state, Physical chemistry
Abstract: Previous detections of methyl and ethyl formate make other small substituted formates potential candidates for observation in the interstellar medium. Among them, vinyl formate is one of the simplest unsaturated carboxylic ester. The aim of this work is to provide direct experimental frequencies of the ground vibrational state of vinyl formate in a large spectral range for astrophysical use. The room-temperature rotational spectrum of vinyl formate has been measured from 80 to 360 GHz and analyzed in terms of Watson's semirigid rotor Hamiltonian. Two thousand six hundred transitions within J = 3-88 and K = 0-28 were assigned to the most stable conformer of vinyl formate and a new set of spectroscopic constants was accurately determined. Spectral features of vinyl formate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of vinyl formate are provided., The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC-2013-SyG, grant agreement No. 610256 NANOCOSMOS, Ministerio de Ciencia e Innovación (Grants CTQ2013-40717-P, AYA2012-32032, and Consolider-Ingenio 2010 CSD2009-00038 program >ASTROMOL>), and Junta de Castilla y Len (grants VA070A08 and VA175U13). J.-C.G. and J.C. thank the ANR-13-BS05-0008 IMOLABS. J.-C.G. thanks the Program PCMI (INSU-CNRS) and the Centre National d'Etudes Spatiales (CNES) for funding support. E.R.A. thanks Ministerio de Ciencia e Innovación for an FPI grant.
Published: 2016
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167. Fourier-transform microwave spectroscopy of a halogen substituted Criegee intermediate ClCHOO

Author: Jean-Claude Guillemin, Carlos Cabezas, Yasuki Endo, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Program PCMI (INSU-CNRS), Centre National d'Etudes Spatiales (CNES), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Fourier transform microwave spectroscopy, Nuclear quadrupole couplings, General Physics and Astronomy, 010402 general chemistry, 01 natural sciences, Criegee intermediate, Computational chemistry, Ab initio quantum chemistry methods, 0103 physical sciences, Kinetic isotope effect, Centrifugal distortion constants, Molecule, Criegee intermediates, [CHIM]Chemical Sciences, Isotopologue, Conformational preferences, Physical and Theoretical Chemistry, Conformational isomerism, 010304 chemical physics, Chemistry, Rotational constants, Molecules, 0104 chemical sciences, Microwave spectroscopy, Physical chemistry, Natural bond orbital analysis, Rotational spectroscopy, Ab initio calculations, Calculations, Natural bond orbital
Abstract: International audience; Pure rotational spectra of the chloro-substituted Criegee intermediate (ClCHOO) were observed by Fourier-transform microwave spectroscopy. Two conformers (syn and anti) of the isolated molecule were identified from the rotational spectra of the parent and 37Cl and 13C isotopologues detected in natural abundance. Rotational constants, centrifugal distortion constants, and all components of the nuclear quadrupole coupling tensor were determined for both conformers. Structural features of the molecule have been rationalized with supporting ab initio calculations and the natural bond orbital analysis, which suggest that the conformational preferences are driven by hyperconjugative effects. © 2016 Author(s).
Published: 2016
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168. Spectroscopic study and astronomical detection of doubly 13 C-substituted ethyl cyanide

Author: Robin T. Garrod, Arnaud Belloche, Jean-Claude Guillemin, Karl M. Menten, Roman A. Motiyenko, Holger S. P. Müller, Laurent Margulès, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Radioastronomie (MPIFR), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Atoms, Cyanide, Analytical chemistry, FOS: Physical sciences, Techniques: spectroscopic, Context (language use), Astrophysics, Spectroscopic analysis, 01 natural sciences, Submillimeter Array, Spectral line, Isotopomers, chemistry.chemical_compound, Isotopes, 0103 physical sciences, [CHIM]Chemical Sciences, Sagittarius B2, Isotopologue, Emission spectrum, 010303 astronomy & astrophysics, Radio lines: ISM, Water vapor, Physics, Cyanides, 010304 chemical physics, Methods: laboratory, Molecular data, Astronomy and Astrophysics, Molecules, Astrophysics - Astrophysics of Galaxies, ISM: molecules, 3. Good health, chemistry, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Quantum theory, ISM: individual objects: Sagittarius B2
Abstract: We have performed a spectral line survey called EMoCA toward Sagittarius B2(N) between 84 and 114 GHz with ALMA. Line intensities of the main isotopic species of ethyl cyanide and its singly 13C-substituted isotopomers observed toward the hot molecular core Sgr B2(N2) suggest that the doubly 13C-substituted isotopomers should be detectable also. We want to determine the spectroscopic parameters of all three doubly 13C-substituted isotopologues of ethyl cyanide to search for them in our ALMA data. We investigated the laboratory rotational spectra of the three species between 150 and 990 GHz. We searched for emission lines produced by these species in the ALMA spectrum of Sgr B2(N2). We modeled their emission as well as the emission of the 12C and singly 13C-substituted isotopologues assuming local thermodynamic equilibrium. We identified more than 5000 rotational transitions, pertaining to more than 3500 different transition frequencies, in the laboratory for each of the three isotopomers. The quantum numbers reach J ~ 115 and K_a ~ 35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations beyond 1000 GHz for strong to moderately weak transitions of either isotopomer. All three species are unambiguously detected in our ALMA data. The 12C/13C column density ratio of the isotopomers with one 13C atom to the ones with two 13C atoms is about 25. Ethyl cyanide is the second molecule after methyl cyanide for which isotopologues containing two 13C atoms have been securely detected in the interstellar medium. The model of our ethyl cyanide data suggests that we should be able to detect vibrational satellites of the main species up to at least v_19 = 1 at 1130 K and up to v_13 + v_21 = 2 at 600 K for the isotopologues with one 13C atom in our present ALMA data. Such satellites may be too weak to be identified unambiguously for isotopologues with two 13C atoms., Comment: accepted for publication in A&A
Published: 2016
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169. Excited electronic structure of methylcyanoacetylene probed by VUV Fourier-transform absorption spectroscopy

Author: Stéphane Douin, Robert Kołos, Nicolas Lamarre, Séverine Boyé-Péronne, L.A. Vieira Mendes, N. de Oliveira, Claudine Crépin, Marcin Gronowski, Bérenger Gans, Jean-Claude Guillemin, Michèle Chevalier, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Instituto de Fisica, Universidade Federal da Bahia (UFBA), Institute of Physical Chemistry, Polska Akademia Nauk = Polish Academy of Sciences (PAN), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), J.-C.G. thanks the Centre National d׳Études Spatiales (CNES) for a grant and the CNRS program Physique et Chimie du Milieu Interstellaire (PCMI) for financial support. R.K. and M.G. acknowledge the support from the National Science Centre (Poland), project no. 2011/03/B/ST4/02763., Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Electronic structure, Materials science, Absorption spectroscopy, Ground state, 02 engineering and technology, 7. Clean energy, 01 natural sciences, Ionization of gases, symbols.namesake, Autoionization, Spacecraft instruments, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Fourier transform infrared spectroscopy, Ionization potential, 010303 astronomy & astrophysics, Spectroscopy, Radiation, Spectrometers, Synchrotron radiation, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Excited states, Rydberg states, 021001 nanoscience & nanotechnology, Bolometers, Fourier series, Atomic and Molecular Physics, and Optics, Fourier transforms, Absorption cross sections, Cyanopropyne, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, 2-Butynenitrile, Excited state, Rydberg formula, symbols, Density functional theory, Fourier transform spectrometers, Rydberg series, Ionization energy, Atomic physics, 0210 nano-technology, Valence electron, Synchrotrons
Abstract: High resolution photoabsorption spectrum of gas-phase methylcyanoacetylene ( CH 3 C 3 N ) has been recorded from 44 500 to 130 000 cm−1 at room temperature with a vacuum ultraviolet Fourier-transform spectrometer on the DESIRS synchrotron beamline (SOLEIL). The absolute photoabsorption cross section in this range is reported for the first time. Valence shell transitions and Rydberg series converging to the ground state X ˜ + E 2 of the cation as well as series converging to electronically excited states ( A ˜ + A 1 2 and C ˜ + ) are observed and assigned. Time-dependent density-functional-theory calculations have been performed to support the assignment of the experimental spectrum in the low energy range. A tentative scaling of the previously measured CH3C3N+ ion yield by Lamarre et al. [17] is proposed, based on the comparison of the absorption data above the first ionization potential with the observed autoionization structures.
Published: 2016
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170. Infrared band intensities of cyanobutadiyne (HC5N) between 400 and 4000cm−1

Author: Yann Trolez, Yves Bénilan, Antoine Jolly, François Raulin, Jean-Claude Guillemin, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, [CHIM.ORGA]Chemical Sciences/Organic chemistry, business.industry, Infrared, Analytical chemistry, Infrared spectroscopy, 010402 general chemistry, 01 natural sciences, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Optics, 0103 physical sciences, Wavenumber, Physical and Theoretical Chemistry, Infrared spectroscopy correlation table, business, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Spectroscopy
Abstract: We report the first infrared spectra of pure gaseous cyanobutadiyne between 400 and 4000 cm −1 . A great care has been taken to obtain a pure sample so that, for the first time, intensities could be determined for all the main bands in the studied domain. The results are compared with available theoretical works. A sample containing a mixture of HC 5 N and DC 5 N was also studied in the same wavenumber range. The data obtained in this study should be very useful to identify those compounds by IR spectroscopy and will allow the quantification of cyanobutadyine in various environments.
Published: 2007
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171. A Microwave and Quantum Chemical Study of the Conformational Properties of Etheneselenocyanate (H2CCHSeC⋮N)

Author: Jean-Claude Guillemin, Harald Møllendal, Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Crystallography, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Chemistry, Excited state, Alkane stereochemistry, Isotopologue, Rotational spectroscopy, Physical and Theoretical Chemistry, Dihedral angle, Triple bond, Conformational isomerism, ComputingMilieux_MISCELLANEOUS, Spectral line
Abstract: The structural and conformational properties of etheneselenocyanate (H2C=CHSeC[triple bond]N) have been explored by microwave spectroscopy and quantum chemical calculations performed at the MP2/aug-cc-pVTZ and B3LYP/aug-cc-pVTZ levels of theory. The spectra of two rotameric forms were assigned. The more stable form has a synperiplanar conformation, whereas the less stable form has an anticlinal conformation characterized by a C-C-Se-C dihedral angle of 163(3) degrees from the synperiplanar position (0 degrees). The synperiplanar form was found to be 4.5(4) kJ/mol more stable than the anticlinal form by relative intensity measurements performed on microwave transitions. The spectra of several isotopologues and two vibrationally excited states were assigned for the synperiplanar conformer. The anticlinal rotamer displays a complicated pattern of low-frequency vibrational states, which is assumed to reflect the existence of a small potential hump at the antiperiplanar (180 degrees) conformation. The predictions made in the MP2 and B3LYP calculations are in reasonably good agreement with the experimental results in some cases, whereas rather large differences are seen for other molecular properties.
Published: 2007
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172. Allenyl and Alkynyl Selenols and Selenocyanates. Synthesis, Spectroscopic Characterization, and Quantum Chemical Study

Author: Gabor Bajor, El Hassan Riague, Jean-Claude Guillemin, Tamás Veszprémi, Brahim Khater, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics [Budapest] (BME), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Quantum chemical, [CHIM.ORGA]Chemical Sciences/Organic chemistry, 010405 organic chemistry, Stereochemistry, Organic Chemistry, Substituent, chemistry.chemical_element, 010402 general chemistry, Hyperconjugation, 01 natural sciences, Medicinal chemistry, 0104 chemical sciences, 3. Good health, Inorganic Chemistry, chemistry.chemical_compound, X-ray photoelectron spectroscopy, chemistry, Atom, Propargyl, Moiety, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS, Selenium
Abstract: Allenyl and alkynyl selenols and selenocyanates with gradually increasing distance between the selenium atom and the unsaturated group have been synthesized and studied by photoelectron spectroscopy and quantum chemical calculations. In the triple-bonded derivatives 1, 2, 5, and 6 (1-alkynylselenium derivatives), an enhanced conjugative interaction was observed, which results in a considerable (0.12−0.13 A) Se−C bond shortening. In the propargyl 3 and 7 and homoallenyl derivatives 10 and 13 a slight but readily well observable hyperconjugation effect could be found. In the case of allenyl selenium derivatives 9 and 12 both effects are in operation, which result in a moderate Se−C bond shortening. With the previously reported study of alkenyl selenium derivatives, the type and extent of the interaction between the SeH or SeCN group and an unsaturated moiety (alkenyl, allenyl, or alkynyl substituent) are now completely clarified.
Published: 2007
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173. Vibronic structure of the 2 Π u ground electronic state of dicyanoacetylene cation revisited by PFI-ZEKE photoelectron spectroscopy and ab initio calculations

Author: Barbara Cunha de Miranda, Christian Alcaraz, Bérenger Gans, Michel Broquier, Séverine Boyé-Péronne, Jacques Liévin, Jean-Claude Guillemin, Nicolas Lamarre, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Centre Laser de l'Université Paris Sud (CLUPS), Université Paris-Sud - Paris 11 (UP11), Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Coupling constant, Renner–Teller effect, PFI-ZEKE PES, Photoemission spectroscopy, Chemistry, ab initio calculations, Biophysics, spin–orbit interaction, Spin–orbit interaction, 2-butynedinitrile, Condensed Matter Physics, 7. Clean energy, Dicyanoacetylene, dicyanoacetylene, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Ab initio quantum chemistry methods, Physics::Atomic and Molecular Clusters, Complete active space, Physical and Theoretical Chemistry, Atomic physics, Ground state, Molecular Biology
Abstract: International audience; (2015): Vibronic structure of the 2 Π u ground electronic state of dicyanoacetylene cation revisited by PFI-ZEKE photoelectron spectroscopy and ab initio calculations, Molecular Physics, The X +2 u ← X 1 + g transition of dicyanoacetylene has been recorded for the first time using pulsed-field-ionisation zero-kinetic-energy photoelectron spectroscopy. The analysis of the photoelectron spectrum allowed an accurate determination of the adiabatic ionisation potential of C 4 N 2 (E i, ad. /hc = 95,479 ± 2 cm −1) and a description of the vibrational structure of the electronic ground state of the cation which is affected by the Renner–Teller effect and the spin–orbit interaction. The spin–orbit coupling constant was measured as −52 ± 2 cm −1. These results are supported by ab initio calculations performed at the complete active space self-consistent field and second-order perturbation theory levels of theory, with extrapolation to the complete basis set limit.
Published: 2015
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174. VUV photoionization and dissociative photoionization spectroscopy of the interstellar molecule aminoacetonitrile: Theory and experiment

Author: Yves Bénilan, M. Mogren Al-Mogren, Majdi Hochlaf, Marie-Claire Gazeau, Lionel Poisson, Jean-Claude Guillemin, Nicolas Fray, A. Bellili, Martin Schwell, Laboratoire de Modélisation et Simulation Multi Echelle (MSME), Université Paris-Est Marne-la-Vallée (UPEM)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Chemistry Department, King Saud University [Riyadh] (KSU), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dynamique Réactionnelle (DyR), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire Interactions, Dynamiques et Lasers (ex SPAM) (LIDyl), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Interactions, Dynamiques et Lasers (ex SPAM) (LIDyl), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), This study was undertaken while M.H. was a Visiting Professor at King Saud University. The support of the Visiting Professor Program at King Saud University is hereby gratefully acknowledged. We are indebted to the general technical staff of Synchrotron Soleil for running the facility. We would like also to thank Gustavo A. Garcia, Laurent Nahon and Jean-François Gil for the excellent support during measurements. We acknowledge financial support from the French National Program Physique et Chimie du Milieu Interstellaire, PCMI (INSU, CNRS) and the 7th European Community Framework Program under COST ACTION CM1405 MOLIM., Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Paris-Est Marne-la-Vallée (UPEM), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Faculty of Science, King Saud University, Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Astrochemistry, Photochemistry, Photoionization mode, Photoelectron photoion coincidence spectroscopy, Photoionization, 010402 general chemistry, 01 natural sciences, Fragmentation (mass spectrometry), Interstellar medium, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Physical and Theoretical Chemistry, Physics::Chemical Physics, Spectroscopy, Physics, Laboratory astrophysics, 010304 chemical physics, Dissociative photoionization, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, 13. Climate action, Potential energy surface, Atomic physics, Ionization energy, VUV spectroscopy
Abstract: International audience; Aminoacetonitrile (AAN) is a key compound in astrochemistry and astrobiology. We present a combined theoretical and experimental investigation concerning the single photoionization of gas-phase AAN and the fragmentation pathways of the resulting cation. At present, we measured photoelectron photoion coincidence (PEPICO) spectra in the 9.8–13.6 eV energy regime using synchrotron radiation as exciting light source. In order to interpret the VUV experimental data obtained, we explored the ground potential energy surface (PES) of AAN and of its cation using standard and explicitly correlated quantum chemical methodologies. This allowed us to deduce accurate thermochemical data for this molecule. We also determined, for the first time, the adiabatic ionization energy of AAN to lie at AIE = (10.085 ± 0.03) eV. The unimolecular decomposition pathways of the resulting AAN+ parent cation are also investigated. The appearance energies of five fragments are determined for the first time, with 30 meV accuracy. Interestingly, our work shows the possibility of the formation of both HCN and HNC isomeric forms. The implications for the evolution of prebiotic molecules under VUV irradiation are briefly discussed.
Published: 2015
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175. ChemInform Abstract: Straightforward Synthesis of 5-Bromopenta-2,4-diynenitrile and Its Reactivity Towards Terminal Alkynes: A Direct Access to Diene and Benzofulvene Scaffolds

Author: Loïc Toupet, Yann Trolez, Lionel Perrin, Paolo Larini, Nicolas Kerisit, and Jean-Claude Guillemin
Subjects: chemistry.chemical_compound, Diene, chemistry, Cascade reaction, chemistry.chemical_element, Diisopropylamine, Reactivity (chemistry), General Medicine, Combinatorial chemistry, Palladium
Abstract: The high-yielding synthesis of 5-bromopenta-2,4-diynenitrile (BrC5N) was achieved for the first time. Its reactivity with triisopropylsilylacetylene and triisopropylsilylbutadiyne in the presence of copper and palladium as co-catalysts and diisopropylamine was evaluated. It revealed an unprecedented cascade reaction leading to a diene in one case and to a benzofulvene in the other case, with a unique structure. Both of them were characterized by X-ray crystallography, among other techniques. The mechanism of the reaction leading to the diene was investigated experimentally. Theoretical calculations at the DFT level suggest that the mechanism leading to the benzofulvene relies on a hexa-dehydro Diels–Alder (HDDA)-type of mechanism. This work constitutes an example of an unanticipated reactivity leading to an important increase of chemical complexity.
Published: 2015
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176. MILLIMETERWAVE SPECTROSCOPY OF ETHANIMINE AND PROPANIMINE AND THEIR SEARCH IN ORION

Author: Jean-Claude Guillemin, José Cernicharo, Roman A. Motiyenko, and L. Margulès
Subjects: chemistry.chemical_compound, Materials science, chemistry, Astronomy, Spectroscopy, Ethanimine
Published: 2015
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177. High temperature sublimation of α-amino acids: a realistic prebiotic process leading to large enantiomeric excess

Author: Valery P. Kukhar, Arkadii V. Tarasevych, Jean-Claude Guillemin, Alexander E. Sorochinsky, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut of Bioorganic Chemistry and Petrochemistry of NASU, National Academy of Sciences of Ukraine (NASU), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [SDV]Life Sciences [q-bio], medicine.medical_treatment, 010402 general chemistry, 01 natural sciences, Catalysis, Phase Transition, Materials Chemistry, medicine, Organic chemistry, Amino Acids, Enantiomeric excess, chemistry.chemical_classification, 010405 organic chemistry, Chemistry, Prebiotic, Metals and Alloys, Temperature, Stereoisomerism, General Chemistry, 0104 chemical sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Amino acid, Enantiopure drug, Ceramics and Composites, Sublimation (phase transition)
Abstract: International audience; The reiterative high temperature co-sublimation of an enantiopure or an enantioenriched α-amino acid mixed with racemic α-amino acids leads to deracemization of the latter. A synergistic effect is observed for complex mixtures, and the sense of the handedness is, for all compounds, identical to that of the enantioenriched starting material.
Published: 2015
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178. Photoionization spectroscopy of CH3C3N in the vacuum-ultraviolet range

Author: Claire Romanzin, Jean-Claude Guillemin, Cyril Falvo, Séverine Boyé-Péronne, Nicolas Lamarre, Christian Alcaraz, A. Flütsch, Stéphane Douin, B. Cunha de Miranda, Bérenger Gans, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), We acknowledge SOLEIL for provision of synchrotron radiation facilities. This work was performed on the DESIRS beamline under proposal number 20131102. J.-C.G. thanks the Centre National d’Etudes Spatiales (CNES) for financial support. The authors acknowledge the computating facility GMPCS of the LUMAT federation (FR LUMAT 2764). The authors would also like to thank J. Lievin for useful discussions., Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Materials science, Dissociative photoionization, Synchrotron radiation, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Photoionization, TPES, DFT calculations, Atomic and Molecular Physics, and Optics, Spectral line, Cyanopropyne, 2-Butynenitrile, Methylcyanoacetylene, Yield (chemistry), [CHIM]Chemical Sciences, Density functional theory, Physical and Theoretical Chemistry, Ionization energy, Atomic physics, Spectroscopy, Adiabatic process
Abstract: International audience; Using vacuum-ultraviolet (VUV) synchrotron radiation, threshold and dissociative photoionization of cyanopropyne (CH3C3N) in the gas phase have been studied from 86 000 cm−1 up to 180 000 cm−1 by recording Threshold-PhotoElectron Spectrum (TPES) and PhotoIon Yield (PIY). Ionization energies of the four lowest electronic states X̃+2E,Ã+2A1,B̃+2E and C̃+ of CH3C3N+ are derived from the TPES with a better accuracy than previously reported. The adiabatic ionization potential of CH3C3N is measured as 86872±20 cm−1. A description of the vibrational structure of these states is proposed leading to the first determination of the vibrational frequencies for most modes. The vibrational assignments of the X̃+ state are supported by density functional theory calculations. In addition, dissociative photoionization spectra have been recorded for several cationic fragments in the range 12–15.5 eV (96 790–125 000 cm−1) and they bring new information on the photophysics of CH3C3N+. Threshold energies for the cationic dissociative channels leading to CH2C3N+, CHC3N+, HC3H+, HCNH+ and CH3+ have been measured for the first time and are compared with quantum chemical calculations.
Published: 2015
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179. Straightforward Synthesis of 5-Bromopenta-2,4-diynenitrile and Its Reactivity Towards Terminal Alkynes: A Direct Access to Diene and Benzofulvene Scaffolds

Author: Jean-Claude Guillemin, Paolo Larini, Lionel Perrin, Nicolas Kerisit, Loïc Toupet, Yann Trolez, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Interface Theory Experiment : Mechanism & Modeling (ITEMM), Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Supérieure Chimie Physique Électronique de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Diene, 010405 organic chemistry, Stereochemistry, Organic Chemistry, chemistry.chemical_element, Diisopropylamine, General Chemistry, 010402 general chemistry, palladium, 01 natural sciences, Combinatorial chemistry, Catalysis, 0104 chemical sciences, acetylenic compounds, hexa-dehydro Diels–Alder reaction, chemistry.chemical_compound, chemistry, Cascade reaction, copper, ynamine, [CHIM]Chemical Sciences, Reactivity (chemistry), Acetylenic Compounds, Palladium
Abstract: International audience; The high-yielding synthesis of 5-bromopenta-2,4-diynenitrile (BrC5N) was achieved for the first time. Its reactivity with triisopropylsilylacetylene and triisopropylsilylbutadiyne in the presence of copper and palladium as co-catalysts and diisopropylamine was evaluated. It revealed an unprecedented cascade reaction leading to a diene in one case and to a benzofulvene in the other case, with a unique structure. Both of them were characterized by X-ray crystallography, among other techniques. The mechanism of the reaction leading to the diene was investigated experimentally. Theoretical calculations at the DFT level suggest that the mechanism leading to the benzofulvene relies on a hexa-dehydro Diels–Alder (HDDA)-type of mechanism. This work constitutes an example of an unanticipated reactivity leading to an important increase of chemical complexity.
Published: 2015
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180. Gas phase dicyanoacetylene (C4N2) on Titan: New experimental and theoretical spectroscopy results applied to Cassini CIRS data

Author: Antoine Jolly, Conor A. Nixon, André Fayt, V. Cottini, Laurent Manceron, Jean-Claude Guillemin, Yves Bénilan, F. Kwabia-Tchana, Patrick G. J. Irwin, Laboratoire inter-universitaire des systèmes atmosphèriques ( LISA ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Université Paris-Est Créteil Val-de-Marne - Paris 12 ( UPEC UP12 ) -Centre National de la Recherche Scientifique ( CNRS ), NASA Goddard Space Flight Center ( GSFC ), Department of Astronomy [College Park], University of Maryland [College Park], Laboratoire de Spectroscopie Moléculaire, Université Catholique de Louvain ( UCL ), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies ( MONARIS ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Synchrotron SOLEIL ( SSOLEIL ), Centre National de la Recherche Scientifique ( CNRS ), Institut des Sciences Chimiques de Rennes ( ISCR ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Ecole Nationale Supérieure de Chimie de Rennes-Institut National des Sciences Appliquées ( INSA ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] ( AOPP ), University of Oxford [Oxford], Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), NASA Goddard Space Flight Center (GSFC), University of Maryland System-University of Maryland System, Université Catholique de Louvain = Catholic University of Louvain (UCL), De la Molécule aux Nanos-objets : Réactivité, Interactions et Spectroscopies (MONARIS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Department of Atmospheric, Oceanic and Planetary Physics [Oxford] (AOPP), Université Catholique de Louvain (UCL), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), University of Oxford, Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: 010504 meteorology & atmospheric sciences, Infrared, [ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph], IR observations, 01 natural sciences, Dicyanoacetylene, [ CHIM ] Chemical Sciences, Spectral line, Hot band, chemistry.chemical_compound, symbols.namesake, Far infrared, [ CHIM.ORGA ] Chemical Sciences/Organic chemistry, 0103 physical sciences, Radiative transfer, [CHIM]Chemical Sciences, Atmosphere of Titan, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Remote sensing, Physics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Atmosphere, Astronomy and Astrophysics, Computational physics, chemistry, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], IR spectroscopy, symbols, Titan (rocket family), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Titan, [ SDU ] Sciences of the Universe [physics]
Abstract: International audience; Dicyanoacetylene has not been observed so far in the gas phase in Titan’s atmosphere but this molecule is still on the list of the detected species, on the basis of the correspondence between a solid phase feature measured at 478 cm−1 in the laboratory and a spectral feature observed by Voyager. In this work, the infrared spectrum of gaseous C4N2 has been investigated to improve our knowledge of the band intensities and the line parameters for this molecule. Results of previously investigated bands have been revised and the intensity of the ν9 band at 107 cm−1, measured for the first time, was found to be the strongest absorption in the whole infrared domain. We have also improved the analysis of the complex rotational and hot band structure of C4N2 in order to obtain the first line lists for both bending modes ν8 and ν9. Using our radiative transfer code including the new line list of the strong ν9 band, we have searched for the signature of C4N2 at 107 cm−1 in the atmosphere of Titan utilizing Titan CIRS far infrared spectra. Despite averaging a large number of CIRS spectra at northern latitudes during the very favorable Titan winter, no gaseous C4N2 could be detected. At the 1-σ level we obtain an abundance upper limit of 5.3 × 10−10 for the limb average which is lower than or comparable to previously inferred values. As a consequence, the absence or very low amount of gaseous C4N2 makes quite puzzling its presence in the solid phase with an abundance compatible with the observed spectral feature at 478 cm−1
Published: 2015
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181. Conformational Properties of cis- and trans-N-Cyclopropylformamide Studied by Microwave Spectroscopy and Quantum Chemical Calculations

Author: Harald Møllendal, Svein Samdal, Jean-Claude Guillemin, Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), 179568/V30, Norges Forskningsråd, Centre National d'Etudes Spatiales, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Cyclopropanes, education.field_of_study, Formamides, Chemistry, Population, Molecular Conformation, Stereoisomerism, Dihedral angle, Spectral line, Crystallography, Computational chemistry, Excited state, Quantum Theory, [CHIM]Chemical Sciences, Rotational spectroscopy, Physical and Theoretical Chemistry, Microwaves, Ground state, education, Conformational isomerism, Cis–trans isomerism
Abstract: International audience; The microwave spectra of cis- and trans-N-cyclopropylformamide, C3H5NHC(═O)H, have been investigated in the 31–123 GHz spectral region at room temperature. Rotational isomerism about the Cring–N bond is possible for both cis and trans. MP2/cc-pVTZ and CCSD/cc-pVTZ calculations indicate that there are two conformers in the case of cis, called Cis I and Cis II, while only one rotamer, denoted Trans, exists for trans-N-cyclopropylformamide. The quantum chemical methods predict that Cis I has an electronic energy that is 8–9 kJ/mol higher than the energy of Cis II. The CCSD H–Cring–N–H dihedral angle is 0.0° in Cis I, 93.0° in Cis II and 79.9° in Trans. The CCSD and MP2 calculations predict a slightly nonplanar structure for the amide moiety in both Trans and Cis II, whereas Cis I is computed to have a planar amide group bisecting the cyclopropyl ring. Surprisingly, the MP2 and CCSD methods predict practically the same energy for Trans and Cis II. The spectra of Cis II in the ground state and in two vibrationally excited states were assigned, while the spectrum of Cis I was not found presumably because of a low Boltzmann population due to a relatively large energy difference (8–9 kJ/mol). The spectra of the ground vibrational state and seven vibrationally excited states of Trans, were assigned. Vibrational frequencies of several of the excited state of both Cis II and Trans were determined by relative intensity measurements. The experimental and CCSD rotational constants are in satisfactory agreement. The MP2 values of the quartic centrifugal distortion constants of both species are in relatively poor agreement with their experimental counterparts. The MP2 vibration–rotation constants and sextic centrifugal distortion constants have little resemblance with the corresponding experimental values.
Published: 2015
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182. Submillimeterwave spectrum of CH2PH and equilibrium structures of CH2PH and CH2NH

Author: Laurent Margulès, P. B. Sreeja, Jean Demaison, Jean-Claude Guillemin, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, 010304 chemical physics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Spectrum (functional analysis), Ab initio, Rotational–vibrational spectroscopy, 010402 general chemistry, 01 natural sciences, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, chemistry.chemical_compound, Nuclear magnetic resonance, Quality (physics), chemistry, 0103 physical sciences, Molecule, Physical chemistry, Physical and Theoretical Chemistry, Methylene, Ground state, ComputingMilieux_MISCELLANEOUS, Spectroscopy, Basis set
Abstract: The rotational spectrum of phosphaethene (CH 2 PH) was reinvestigated. One hundred and nineteen new lines were measured in the submillimeter range from 500 to 650 GHz. The determination of the centrifugal distortion constants is significantly improved. As the molecule is close to symmetric prolate top, both reduction A and S were compared. The equilibrium structure has been derived from experimental ground state rotational constants and ab initio rovibrational interaction parameters. This semi-experimental structure is in excellent agreement with the ab initio structure calculated at the CCSD(T) level of theory using a basis set of quintuple-zeta quality and a core correlation correction. The structure of CH 2 PH was compared to that of CH 2 NH which was also determined for this goal. It is found that the semi-experimental structure of CH 2 NH is less accurate than the ab initio structure. It is also found that the methylene group is much more asymmetric in CH 2 NH than in CH 2 PH.
Published: 2006
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183. Conformational Composition of Cyclopentadienylphosphine Investigated by Microwave Spectroscopy and Quantum Chemical Calculations

Author: Jean-Claude Guillemin, Harald Møllendal, George C. Cole, Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Models, Molecular, Cyclopentadiene, Phosphines, Molecular Conformation, Cyclopentanes, 010402 general chemistry, Ring (chemistry), 01 natural sciences, Spectral line, chemistry.chemical_compound, Computational chemistry, 0103 physical sciences, Physical and Theoretical Chemistry, Microwaves, Conformational isomerism, ComputingMilieux_MISCELLANEOUS, Basis set, 010304 chemical physics, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Chemistry, Hydrogen bond, Spectrum Analysis, Hydrogen Bonding, 0104 chemical sciences, Crystallography, Intramolecular force, Quantum Theory, Rotational spectroscopy
Abstract: The properties of cyclopentadienylphosphine have been investigated by means of Stark-modulation microwave spectroscopy and quantum chemical calculations at the MP2/aug-cc-pVTZ, B3LYP/6-311++G(d,p), and G3 levels of theory. Spectra attributable to two rotamers denoted conformers I and II have been assigned. Conformer I has a symmetry plane (Cs symmetry) consisting of the bisectors of the cyclopentadiene ring and of the phosphino group with the lone electron pair of phosphorus pointing toward the carbon ring. In conformer II, the phosphino group is rotated approximately 120 degrees out of this plane. Relative intensity measurements have been made, and it was found that conformer II is more stable than I by 1.3(4) kJ/mol. The preferred conformer represents a borderline case of intramolecular hydrogen bond stabilization. The experimental and MP2/ aug-cc-pVTZ rotational constants differ by several percent, which indicates that the aug-cc-pVTZ basis set is not large enough to be able to predict an accurate structure for the two conformers that are close to the equilibrium geometries. 5-Substituted 1,3-cyclopentadienyl derivatives may undergo circumambulatory rearrangements. However, there is no manifestation of this effect in the microwave spectrum of cyclopentadienylphosphine.
Published: 2005
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184. Olefin metathesis in room temperature ionic liquids using imidazolium-tagged ruthenium complexes

Author: Hervé Clavier, Nicolas Audic, Marc Mauduit, and Jean-Claude Guillemin
Subjects: Olefin fiber, Olefin metathesis, Organic Chemistry, chemistry.chemical_element, General Medicine, Metathesis, Biochemistry, Catalysis, Ruthenium, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Ionic liquid, Salt metathesis reaction, Materials Chemistry, Organic chemistry, Reactivity (chemistry), Physical and Theoretical Chemistry
Abstract: New recyclable imidazolium-tagged ruthenium catalysts have been developed to perform olefin metathesis in room temperature ionic liquids (RTILs). High level of recyclability combined with a high reactivity were obtained in the ring-closing metathesis (RCM) of a variety of di- or tri-substituted and/or oxygen-containing dienes. Extremely low residual ruthenium levels were detected in the RCM products (average of 7.3 ppm per run). Several examples of olefin cross-metathesis (CM) have been also studied.
Published: 2005
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185. New bidentate alkoxy-NHC ligands for enantioselective copper-catalysed conjugate addition

Author: Hervé Clavier, Jean-Claude Guillemin, Marc Mauduit, and Ludovic Coutable
Subjects: Denticity, Organic Chemistry, Enantioselective synthesis, chemistry.chemical_element, Medicinal chemistry, Copper, Catalysis, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Alkoxy group, Organic chemistry, Physical and Theoretical Chemistry, Enantiomer, Carbene, Conjugate
Abstract: Chiral alkoxy-imidazolinium salts are easily available via a five-step procedure starting from β-aminoalcohols. This new family of alkoxy-N-heterocyclic carbene (NHC) precursors is shown to be highly active in the enantioselective copper-catalysed conjugate addition to cyclic enones. Complete conversion with low catalyst loading and good enantiomeric excesses up to 93% were obtained at room temperature.
Published: 2005
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186. Acidity Trends in α,β-Unsaturated Sulfur, Selenium, and Tellurium Derivatives: Comparison with C-, Si-, Ge-, Sn-, N-, P-, As-, and Sb-Containing Analogues

Author: Jean-Claude Guillemin, El Hassan Riague, Jean-François Gal, Otilia Mó, Pierre-Charles Maria, and Manuel Yáñez
Subjects: Degree of unsaturation, Organic Chemistry, Heteroatom, chemistry.chemical_element, General Medicine, Electrolyte, General Chemistry, Sulfur, Tautomer, Medicinal chemistry, Catalysis, Fourier transform ion cyclotron resonance, Electronegativity, Chalcogen, chemistry, Organic chemistry, Selenium
Abstract: The gas-phase acidity of CH3-CH2XH (X=S, Se, Te), CH2=CHXH (X=S, Se, Te) and PhXH (X=S, Se) compounds was measured by means of Fourier transform ion cyclotron resonance mass spectrometry. To analyze the role that unsaturation plays on the intrinsic acidity of these systems, a parallel theoretical study, in the framework of the G2 and the G2(MP2) theories, was carried out for all ethyl, ethenyl (vinyl), ethynyl, and phenyl O-, S-, Se-, and Te-containing derivatives. Unsaturated compounds are stronger acids than their saturated analogues, because of the strong pi-electron donor ability of the heteroatoms that contributes to a large stabilization of the unsaturated anions. Ethynyl derivatives are stronger acids than vinyl compounds, while phenyl derivatives have an intrinsic acidity intermediate between that of the corresponding vinyl and ethynyl analogues. The CH2=CHXH vinyl compounds (enol-like) behave systematically as slightly stronger acids than their CH3-C(H)X (keto-like) tautomers. Vinyl derivatives are stronger acids than ethyl compounds, because the anion stabilization attributable to unsaturation is greater than that undergone in the neutral compounds. Conversely, the enhanced acidity of the ethynyl derivatives with respect to the vinyl compounds is due to two concomitant effects, the stabilization of the anion and the destabilization of the neutral compound. The acidities of ethyl, vinyl, and ethynyl derivatives containing heteroatoms of Groups 14, 15, and 16 of the periodic table are closely related, and reflect the differences in electronegativity of the CH3CH2-, CH2=CH-, and CH[triple chemical bond]C- groups.
Published: 2005
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187. Alkenyl Selenols and Selenocyanates: Synthesis, Spectroscopic Characterization by Photoelectron Spectroscopy, and Quantum Chemical Study

Author: Jean-Claude Guillemin, Tamás Veszprémi, El Hassan Riague, and Gabor Bajor
Subjects: chemistry.chemical_classification, Double bond, Organic Chemistry, chemistry.chemical_element, General Chemistry, Photochemistry, Hyperconjugation, Catalysis, chemistry, X-ray photoelectron spectroscopy, Ab initio quantum chemistry methods, Group (periodic table), Polymer chemistry, Lone pair, Conformational isomerism, Selenium
Abstract: Vinyl, allyl, and homoallyl selenols were easily prepared by a chemoselective reduction of the corresponding selenocyanates with aluminum hydrides. Two stable vinyl and five stable allyl conformers of both series were predicted on the potential-energy surface. The interaction of SeH or SeCN groups with the vinyl group has been investigated with UV photoelectron spectroscopy and quantum chemical calculations, using the MP2/ cc-pVTZ and B3LYP/cc-pVTZ levels. In the vinyl derivatives, a surprisingly strong direct conjugation of the selenium lone electron pair and the C=C double bond was observed. On the other hand, in allyl position the selenium lone pair is independent on the C= C double bond, and the hyperconjugation between the Se-C bond and the double bond is the ruling effect. Thus is clarified the type and extent of the interaction between the Sell or SeCN group and the unsaturated moicty.
Published: 2004
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188. Intramolecular coupling of acetylenic groups of bis(alkynyl)phosphanes and silanes mediated by benzynezirconocene: a route to new mono- and tricyclic heterocycles

Author: Alain Igau, Philippe Meunier, Nadine Pirio, Peter Schuetz, Bruno Donnadieu, Jean-Pierre Majoral, Jean-Claude Guillemin, Laurence Dupuis, and Stephane Bredeau
Subjects: chemistry.chemical_classification, Silanes, Chemistry, Organic Chemistry, Heteroatom, Thermal decomposition, General Medicine, Photochemistry, Ring (chemistry), Biochemistry, Medicinal chemistry, Coupling (electronics), chemistry.chemical_compound, C c coupling, Main group element, Intramolecular force, Polymer chemistry, Drug Discovery, Tricyclic
Abstract: Benzo-zirconacyclohexadiene-phospha or silacyclobutene fused ring systems are easily prepared via a benzynezirconocene intermediate by means of thermolysis of Cp 2 ZrPh 2 in the presence of bis(alkynyl)phosphanes or silanes. These polyunsaturated systems are the source of a variety of new mono- or tricyclic heterocycles incorporating either one or two heteroatoms.
Published: 2004
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189. 3-ButeneselenolThe First Example of a Selenol with an Intramolecular Hydrogen Bond as Studied by Microwave Spectroscopy and Quantum Chemical Calculations

Author: Harald Møllendal, Denis Petitprez, Jean-Claude Guillemin, Jean Demaison, and Georges Wlodarczak
Subjects: chemistry.chemical_classification, Double bond, Hydrogen bond, Selenol, Hydrogen atom, Photochemistry, chemistry.chemical_compound, chemistry, Intramolecular force, Physical chemistry, Rotational spectroscopy, Physical and Theoretical Chemistry, Conformational isomerism, Microwave
Abstract: The microwave spectrum of 3-buteneselenol (H2CdCH-CH2-CH2SeH) has been investigated in the 24-62 GHz spectral range by Stark microwave spectroscopy and by Fourier transform microwave spectroscopy in the 6-20 GHz region. High-level quantum chemical calculations carried out for 14 conformers predict that their energies fall within a narrow range of less than 7 kJ/mol. The most stable conformer was predicted to have an intramolecular hydrogen bond formed between the hydrogen atom of the selenol group and the double bond. The microwave spectra of the three most stable conformers were assigned. One of these rotamers has an internal hydrogen bond, whereas the two others are without this interaction. It was found by relative intensity measurements that the hydrogen-bonded conformer is 1.6(7) and 1.9(5) kJ/mol, respectively, more stable than the two other rotamers. As far as we know, this is the first example of a gas-phase study demonstrating that a selenol indeed participates in intramolecular hydrogen bonding.
Published: 2004
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190. Prebiotic, planetary and interstellar chemistry starting from compounds detected in the interstellar medium

Author: El Hassan Riague, Miloud Bouyahyi, and Jean-Claude Guillemin
Subjects: Atmospheric Science, Astrochemistry, Liquid water, Chemistry, Prebiotic, medicine.medical_treatment, Aerospace Engineering, Astronomy and Astrophysics, Astrobiology, Interstellar medium, Prebiotic chemistry, chemistry.chemical_compound, Geophysics, Space and Planetary Science, Phase (matter), medicine, General Earth and Planetary Sciences, Organic synthesis
Abstract: The most important families of reagents used in organic synthesis are represented in the 130 compounds detected up-to-now in the interstellar medium. The ability of these compounds to react together in the gaseous phase or in liquid water is discussed. Some examples of the possible formation of various products in such media are presented.
Published: 2004
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191. Microwave Spectrum and Molecular Structure of Etheneselenol

Author: Jean-Claude Guillemin, Georges Wlodarczak, El Hassan Riague, Denis Petitprez, and Jean Demaison
Subjects: Coupling constant, Quantitative Biology::Biomolecules, Deuterium, Chemistry, Ab initio quantum chemistry methods, Quadrupole, Analytical chemistry, Molecule, Physical and Theoretical Chemistry, Molecular physics, Conformational isomerism, Microwave, Spectral line
Abstract: The rotational spectrum of etheneselenol was investigated in the microwave and millimeter-wave ranges. Two conformers of comparable stability were identified: the syn conformer, which is planar, and the gauche conformer. The experimental study has been coupled with some ab initio calculations, which greatly helped to the identification of the spectra. The etheneselenol-d (Se-D) was also investigated and the quadrupole coupling constants of deuterium determined.
Published: 2003
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192. Ultraviolet and infrared spectrum of C6H2 revisited and vapor pressure curve in Titan's atmosphere

Author: François Raulin, Jean-Claude Guillemin, Yves Bénilan, Antoine Jolly, F. Shindo, and Patrick Chaquin
Subjects: Diacetylene, Infrared, Vapor pressure, Analytical chemistry, Astronomy and Astrophysics, Atmospheric temperature range, Atmospheric sciences, chemistry.chemical_compound, symbols.namesake, chemistry, Enthalpy of sublimation, Space and Planetary Science, symbols, Thermosphere, Titan (rocket family), Stratosphere
Abstract: The presence of the linear molecules called polyynes, (C2nH2, n>2), in Titan's atmosphere is suggested by the signatures of acetylene C2H2 and of diacetylene C4H2 in Voyager spectra. Both atmospheric simulations and photochemical modelling support polyynes implication in Titan's chemistry as an interface between the gaseous phase and the solid phase visible in aerosols form. However, the detection of polyynes higher than C4H2 depends on our ability to determine their spectra in the laboratory under low temperature and pressure conditions. We revisit here spectroscopic investigations on triacetylene, C6H2, since previous UV and IR measurements suffered from great uncertainty, respectively, due to an impurity contribution and saturation effects. We point out the importance of studying a pure sample and we underline the strong temperature dependency of UV absolute absorption coefficients (185– 320 nm ). In the IR range (220– 4300 cm −1 ), our determination of the absolute intensity of the main bands is 30% higher than previous measurements. For the first time, the vapor pressure law of triacetylene is investigated in a limited temperature range (170– 200 K ) allowing a calculation of its enthalpy of sublimation. Those results applied to Titan's atmospheric conditions show the possible existence of two condensation regions: one located in the low stratosphere (∼100 km ) and the other in thermosphere (∼700 km ) . The condensation at an altitude of 700 km is consistent with the observation of an upper haze layer. This could imply the presence of a heterogeneous chemistry but also an inhibition of the polyynes formation, not included in available photochemical models.
Published: 2003
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193. Acidity enhancement of unsaturated bases of group 15 by association with borane and beryllium dihydride. Unexpected boron and beryllium Brønsted acids

Author: Manuel Yáñez, Jean-Claude Guillemin, Ana Martín-Sómer, Otilia Mó, Departemento de Química C-9, Universidad Autonoma de Madrid (UAM), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Universidad Autónoma de Madrid (UAM), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and UAM. Departamento de Química Orgánica
Subjects: Heteroatom, Inorganic chemistry, chemistry.chemical_element, Borane, Medicinal chemistry, Inorganic Chemistry, chemistry.chemical_compound, Minimum value, Molecule, [CHIM]Chemical Sciences, Molecular orbital, Lewis acids and bases, Lewis Acid, Phosphorus compounds, Dihydrides, Química, Molecules, Triple bond, Unsaturated compounds, Level density, chemistry, Molecular orbitals, Heteroatoms, Density functional theory, Beryllium, Ab initio calculations, Triple bonds, Brønsted–Lowry acid–base theory, Calculations, Ethynyl
Abstract: The intrinsic acidity of CH2=CHXH2, HC=CXH2 (X = N, P, As, Sb) derivatives and of their complexes with BeH2 and BH3 has been investigated by means of high-level density functional theory and molecular orbital ab initio calculations, using as a reference the ethyl saturated analogues. The acidity of the free systems steadily increases down the group for the three series of derivatives, ethyl, vinyl and ethynyl. The association with both beryllium dihydride and borane leads to a very significant acidity enhancement, being larger for BeH2 than for BH3 complexes. This acidity enhancement, for the unsaturated compounds, is accompanied by a change in the acidity trends down the group, which do not steadily decrease but present a minimum value for both the vinyl- and the ethynyl-phosphine. When the molecule acting as the Lewis acid is beryllium dihydride, the π-type complexes in which the BeH2 molecules interact with the double or triple bond are found, in some cases, to be more stable, in terms of free energies, than the conventional complexes in which the attachment takes place at the heteroatom, X. The most important finding, however, is that P, As, and Sb ethynyl complexes with BeH2 do not behave as P, As, or Sb Brønsted acids, but unexpectedly as Be acids, This work was partially supported by the Ministerio de Economía y Competitividad (project no. CTQ2012-35513-C02-01), by the CMST COST Action CM1204, and by the Project MADRISOLAR2, Ref.: S2009PPQ/1533 of the Comunidad Autónoma de Madrid. AMS acknowledges a FPI contract from the Ministerio de Economía y Competitividad of Spain.
Published: 2015
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194. The Electronic Structure of Some Cyanohydrins-A Spectroscopically Under-Investigated Family of Compounds

Author: Anna Chrostowska, Abdessamad Benidar, Clovis Darrigan, Alain Dargelos, Jean-Claude Guillemin, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Centre National d’Etudes Spatiales, Conseil National de la Recherche Scientifique, Institut pluridisciplinaire de recherche sur l'environnement et les matériaux (IPREM), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Glycolonitrile, ab initio calculations, photoelectron spectroscopy, Hydrogen cyanide, Infrared spectroscopy, Electronic structure, Atomic and Molecular Physics, and Optics, chemistry.chemical_compound, symbols.namesake, chemistry, X-ray photoelectron spectroscopy, Computational chemistry, Ab initio quantum chemistry methods, IR spectroscopy, Raman spectroscopy, symbols, Organic chemistry, [CHIM]Chemical Sciences, Thermal stability, cyanohydrins, Physical and Theoretical Chemistry
Abstract: International audience; Cyanohydrins are usually formed by addition of hydrogen cyanide to aldehydes or ketones while the elimination of HCN from cyanohydrins is easily observed upon heating. The low thermal stability of these highly boiling compounds leads to difficult studies in the gas phase where partial or complete decomposition is usually observed. Consequently, the reported physicochemical properties of such compounds in the gas phase are still scarce. Keeping with this, four simple cyanohydrins, the glycolonitrile and methyl, vinyl and ethynyl derivatives, have been selected. These are possible candidates for the Interstellar Medium, where the corresponding aldehydes and HCN have been detected, and could have played an important role in prebiotic chemistry, as already proposed for some of them. Three well-suited spectroscopic techniques, namely, UV photoelectron, infrared, and Raman spectroscopies, in tandem with quantum calculations, have been chosen for the structure analysis. Photoelectron spectroscopy, successfully performed with gaseous compounds, provides the first comparative study on cyanohydrins in the gas phase.
Published: 2015
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195. Microwave and Quantum-Chemical Study of Conformational Properties and Intramolecular Hydrogen Bonding of 2-Hydroxy-3-Butynenitrile (HC≡CCH(OH)C≡N)

Author: Svein Samdal, Jean-Claude Guillemin, Harald Møllendal, Centre for Theoretical and Computational Chemistry [Oslo] (CTCC), Department of Chemistry [Oslo], Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO)-Faculty of Mathematics and Natural Sciences [Oslo], University of Oslo (UiO)-University of Oslo (UiO), Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), 179568/V30, Norges Forskningsråd, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010304 chemical physics, Hydrogen bond, Chemistry, Hydrogen atom, 010402 general chemistry, Photochemistry, 01 natural sciences, Spectral line, 0104 chemical sciences, Crystallography, Deuterium, Intramolecular force, Excited state, 0103 physical sciences, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, Conformational isomerism, Microwave
Abstract: International audience; The microwave spectra of 2-hydroxy-3-butynenitrile, HC≡CCH(OH)C≡N, and a deuterated species, HC≡CCH(OD)C≡N, have been investigated in the 38-120 GHz spectral region. Three rotameric forms, each stabilized by intramolecular hydrogen bonds, are possible for this compound. The hydrogen atom of the hydroxyl group is hydrogen-bonded to the π electrons of the alkynyl group in one of these conformers, to the π electrons of the cyano group in the second rotamer, and to both of these groups simultaneously in the third conformer. The microwave spectra of the parent and deuterated species of last-mentioned form have been assigned, and accurate values of the rotational and quartic centrifugal distortion constants of these species have been determined. The spectra of two vibrational excited states of this conformer have also been assigned, and their frequencies have been determined by relative intensity measurements. Quantum-chemical calculations at the MP2/cc-pVTZ and CCSD/cc-pVQZ levels were performed to assist the microwave work. The theoretical predictions were generally found to be in good agreement with observations.
Published: 2015
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196. ChemInform Abstract: High-Yield Formation of Substituted Tetracyanobutadienes (III) from Reaction of Ynamides (I) with Tetracyanoethylene

Author: Nicolas Kerisit, Jean-Claude Guillemin, Claudine Katan, Yann Trolez, Yann R. Leroux, Jean-François Halet, Marie Betou, and Esme Meledje
Subjects: chemistry.chemical_compound, Chemistry, Yield (chemistry), General Medicine, Tetracyanoethylene, Medicinal chemistry
Published: 2015
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197. Searching for trans ethyl methyl ether in Orion KL

Author: A. López, Jean-Claude Guillemin, N. Brouillet, L. Kolesniková, José L. Alonso, Laurent Margulès, Belén Tercero, José Cernicharo, Roman A. Motiyenko, Ministerio de Ciencia e Innovación (España), European Research Council, Ministerio de Economía y Competitividad (España), Dpt. Astrofisica Molecular e Infrarroja, CSIS - IEM, Departamento de Astrofísica Molecular e Infrarroja (DAMIR), Instituto de Estructura de la Materia (IEM), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), FORMATION STELLAIRE 2015, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidad de Valladolid-CSIC, Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 (PhLAM), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: ISM: individual objects: Orion KL, individual objects (Orion KL), Spin states, [SDU.ASTR.CO]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Analytical chemistry, FOS: Physical sciences, Ether, Astrophysics, clouds, Surveys, ISM: clouds, ISM: abundances, Article, individual objects: Orion KL [ISM], chemistry.chemical_compound, surveys, Molecule, molecules, Radio lines: ISM, molecules [ISM], Line (formation), Physics, abundances [ISM], abundances, Astronomy and Astrophysics, Rotational temperature, Astrophysics - Astrophysics of Galaxies, ISM: molecules, ISM [Radio lines], chemistry, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), radio lines, clouds [ISM]
Abstract: We report on the tentative detection of $trans$ Ethyl Methyl Ether (tEME), $t-CH_3CH_2OCH_3$, through the identification of a large number of rotational lines from each one of the spin states of the molecule towards Orion KL. We also search for $gauche$-$trans$-n-propanol, $Gt-n-CH_3CH_2CH_2OH$, an isomer of tEME in the same source. We have identified lines of both species in the IRAM 30m line survey and in the ALMA Science Verification data. We have obtained ALMA maps to establish the spatial distribution of these species. Whereas tEME mainly arises from the compact ridge component of Orion, Gt-n-propanol appears at the emission peak of ethanol (south hot core). The derived column densities of these species at the location of their emission peaks are $\leq(4.0\pm0.8)\times10^{15} cm^{-2}$ and $\leq(1.0\pm0.2)\times10^{15} cm^{-2}$ for tEME and Gt-n-propanol, respectively. The rotational temperature is $\sim100 K$ for both molecules. We also provide maps of $CH_3OCOH$, $CH_3CH_2OCOH$, $CH_3OCH_3$, $CH_3OH$, and $CH_3CH_2OH$ to compare the distribution of these organic saturated O-bearing species containing methyl and ethyl groups in this region. Abundance ratios of related species and upper limits to the abundances of non-detected ethers are provided. We derive an abundance ratio $N(CH_3OCH_3)/N(tEME)\geq150$ in the compact ridge of Orion., Accepted in A&A Letters
Published: 2015
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198. Attrition-induced spontaneous chiral amplification of the γ polymorphic modification of glycine

Author: Jean-Claude Guillemin, Arkadii V. Tarasevych, Jeanne Crassous, Alexander E. Sorochinsky, Loïc Toupet, Valery P. Kukhar, Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Institut of Bioorganic Chemistry and Petrochemistry of NASU, National Academy of Sciences of Ukraine (NASU), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Alanine, Ostwald ripening, chemistry.chemical_classification, 010405 organic chemistry, Stereochemistry, Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, technology, industry, and agriculture, food and beverages, General Chemistry, Optically active, 010402 general chemistry, Condensed Matter Physics, 01 natural sciences, 0104 chemical sciences, Amino acid, symbols.namesake, Glycine, symbols, Racemic mixture, General Materials Science, Enantiomer
Abstract: International audience; Glycine is the simplest achiral amino acid that undergoesspontaneous mirror symmetry breaking when it crystallizes in itschiral γ-polymorphic modification. As a result of Ostwaldripening, its racemic mixture stochastically becomes opticallyactive. The sense of the resulting handedness can be controlled byaddition of one enantiomer of a simple chiral amino acid, thealanine.
Published: 2015
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199. FT-ICR studies of anionic reactions for the chemistry of planetary ionospheres

Author: Jan Zabka, Miroslav Polášek, Joël Lemaire, Claire Romanzin, Essyllt Louarn, Christian Alcaraz, Jean-Claude Guillemin, Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: History, Spectrometer, Chemistry, Analytical chemistry, 7. Clean energy, Computer Science Applications, Education, Astrobiology, Interstellar medium, symbols.namesake, Reaction rate constant, 13. Climate action, Physics::Space Physics, symbols, Molecule, [CHIM]Chemical Sciences, Physics::Chemical Physics, Ionosphere, Nuclear Experiment, Titan (rocket family), Astrophysics::Galaxy Astrophysics
Abstract: International audience; The rate constants of several ion-molecule reactions involving CN − and C 3 N − anions and HC 3 N molecules have been measured in a FT-ICR spectrometer. These measurements are of particular importance for the chemistry of Titan's ionosphere and interstellar medium
Published: 2015
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200. Structure, spectroscopy, and thermal decomposition of 5-chloro-1,2,3,4-thiatriazole: a He I photoelectron, infrared, and quantum chemical study

Author: Gábor Vass, Jean-Claude Guillemin, Tibor Pasinszki, Dániel Dzsotján, Institute of Chemistry [Budapest], Faculty of Sciences [Budapest], Eötvös Loránd University (ELTE)-Eötvös Loránd University (ELTE), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), We thank the Hungarian Scientific Research Fund for financial support to the project (grant no. OTKA K101164)., Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Electronic structure, UPS, 010402 general chemistry, 01 natural sciences, 7. Clean energy, DFT, Physical Chemistry, X-ray photoelectron spectroscopy, Computational chemistry, Theoretical and Computational Chemistry, Ionization, Molecule, [CHIM]Chemical Sciences, Computer Applications in Chemistry, Physical and Theoretical Chemistry, Spectroscopy, Basis set, 010405 organic chemistry, Chemistry, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Thermal decomposition, Structure, Molecular orbital theory, Condensed Matter Physics, 0104 chemical sciences, 3. Good health, Ab initio, IR, Thermolysis
Abstract: International audience; 5-Chloro-1,2,3,4-thiatriazole has been investigated in the gas phase for the first time by mid-infrared and He I photoelectron spectroscopy. The ground-state geometry has been obtained from quantum chemical calculations at the CCSD(T) and B3LYP levels using aug-cc-pVTZ basis set. Ionization potentials have been determined and the electronic structure has been discussed within the frame of molecular orbital theory. IR and photoelectron spectroscopies, supported by quantum chemical calculations at the B3LYP and SAC-CI levels, provide a detailed investigation into the vibrational and electronic character of the molecule. Thermal stability of 5-chloro-1,2,3,4-thiatriazole has been studied both experimentally and theoretically. Flash vacuum thermolysis of the molecule produces fast quantitatively N2, ClCN, and sulfur. Theoretical calculations at the CCSD(T)//B3LYP level predict competitive decomposition routes, starting either with a retro-cycloaddition reaction leading to N2S and ClCN or with a ring opening to chlorothiocarbonyl azide intermediate, to produce finally N2, S, and ClCN. Calculations also predict that N2S is reactive and decomposes in bimolecular reactions to N2 and S2
Published: 2015
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