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1. Photochemical formation of thiirene and thioketene in 1,2,3-thiadiazoles with phenyl substituents studied by time-resolved spectroscopy

Author

Tomasz Pedzinski, Michel Sliwa, Gotard Burdzinski, Julien Réhault, Yunlong Zhang, Stéphanie Delbaere, Quantum Electronics Laboratory, Adam Mickiewicz University in Poznań (UAM), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Koch Institute for Cancer Research, Massachusetts Institute of Technology (MIT), Faculty of Chemistry, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
Time Factors, Spectrophotometry, Infrared, Ultraviolet Rays, 010402 general chemistry, Photochemistry, 01 natural sciences, Thioketene, chemistry.chemical_compound, Isomerism, Thiadiazoles, Ultrafast laser spectroscopy, Singlet state, Physical and Theoretical Chemistry, Photolysis, 010405 organic chemistry, Intermolecular force, Temperature, Ethylenes, Ketones, 0104 chemical sciences, Thiirene, Solutions, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry, Excited state, Spectrophotometry, Ultraviolet, Time-resolved spectroscopy
Abstract

Photochemistry of 4-phenyl-1,2,3-thiadiazole (PT) and 4,5-diphenyl-1,2,3-thiadiazole (DPT) in solution was studied at room temperature using UV-vis and IR transient absorption spectroscopies (λex = 266 nm). Ultrafast techniques show a very fast rise (

Published
2013
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2. Orbital breathing effects in the computation of x-ray d-ion spectra in solids by ab initio wave-function-based methods

Author

Hermann Stoll, Claude Monney, Jochen Geck, Alexander O. Mitrushchenkov, Nikolay A. Bogdanov, Roberto Kraus, Thorsten Schmitt, Liviu Hozoi, Valentina Bisogni, Jeroen van den Brink, Ke-Jin Zhou, Max Planck Institute for Solid State Research, Max-Planck-Gesellschaft, Leibniz Institute for Solid State and Materials Research (IFW Dresden), Leibniz Association, Brookhaven National Laboratory Mational Synchrotron Light Source (BNL NSLS), Brookhaven National Laboratory, The Swiss Light Source (SLS) (SLS-PSI), Paul Scherrer Institute (PSI), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] (UZH), STFC, ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, STFC, ISIS Facility, University of Salzburg, Laboratoire de Modélisation et Simulation Multi Echelle (MSME), 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), Universität Stuttgart [Stuttgart], Brookhaven National Laboratory [Upton, NY] (BNL), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Universität Zürich [Zürich] = University of Zurich (UZH), ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​ISIS Neutron and Muon Source (ISIS), STFC Rutherford Appleton Laboratory (RAL), Science and Technology Facilities Council (STFC)-Science and Technology Facilities Council (STFC), 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), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), and State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE)

Subjects
ab initio computational methods, Ab initio, FOS: Physical sciences, 02 engineering and technology, core-hole potential, 01 natural sciences, Molecular physics, Spectral line, Ion, Condensed Matter - Strongly Correlated Electrons, 0103 physical sciences, General Materials Science, Cuprate, 010306 general physics, Wave function, resonant inelastic x-ray scattering (RIXS), Physics, Strongly Correlated Electrons (cond-mat.str-el), Scattering, transition-metal oxides, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Polarization (waves), [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Relaxation (physics), 0210 nano-technology
Abstract

International audience; In existing theoretical approaches to core-level excitations of transition-metal ions in solids relaxation and polarization effects due to the inner core hole are often ignored or described phenomenologically. Here we set up an ab initio computational scheme that explicitly accounts for such physics in the calculation of x-ray absorption and resonant inelastic x-ray scattering spectra. Good agreement is found with experimental transition-metal L-edge data for the strongly correlated d9 cuprate Li2CuO2, for which we determine the absolute scattering intensities. The newly developed methodology opens the way for the investigation of even more complex dn electronic structures of group VI B to VIII B correlated oxide compounds.

Published
2017
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3. From molten salts to room temperature ionic liquids: simulation studies on chloroaluminate systems

Author

Mathieu Salanne, Barbara Kirchner, Paul A. Madden, Ari P. Seitsonen, Leonardo J. A. Siqueira, Physicochimie des Electrolytes, Colloïdes et Sciences Analytiques (PECSA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laborat orio de Materiais H ibridos, Universidade Federal de Sao Paulo, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Materials, University of Oxford, Chemie, Universität Leipzig, Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC), University of Oxford [Oxford], Universität Leipzig [Leipzig], University of Zurich, and Salanne, Mathieu

Subjects
10120 Department of Chemistry, Aluminium chloride, Materials science, Analytical chemistry, Ionic Liquids, FOS: Physical sciences, Car-Parrinello, Electronic structure, Molecular Dynamics Simulation, 010402 general chemistry, 01 natural sciences, Chloride, Ion, chemistry.chemical_compound, Molecular dynamics, polarizable force field, Electrical resistivity and conductivity, Physics - Chemical Physics, 540 Chemistry, 0103 physical sciences, RTIL, medicine, Organometallic Compounds, Physical and Theoretical Chemistry, ionic liquid, Chemical Physics (physics.chem-ph), Condensed Matter - Materials Science, Ionic radius, 010304 chemical physics, Temperature, Materials Science (cond-mat.mtrl-sci), molecular dynamics, 0104 chemical sciences, chemistry, Ionic liquid, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Salts, 1606 Physical and Theoretical Chemistry, medicine.drug, Aluminum
Abstract

International audience; An interaction potential including chloride anion polarization effects, constructed from first-principles calculations, is used to examine the structure and transport properties of a series of chloroaluminate melts. A particular emphasis was given to the study of the equimolar mixture of aluminium chloride with 1-ethyl-3-methylimidazolium chloride, which forms a room temperature ionic liquid EMI-AlCl 4. The structure yielded by the classical simulations performed within the framework of the polarizable ion model is compared to the results obtained from entirely electronic structure-based simulations: An excellent agreement between the two flavors of molecular dynamics is observed. When changing the organic cation EMI+ by an inorganic cation with a smaller ionic radius (Li+, Na+, K+), the chloroaluminate speciation becomes more complex, with the formation of Al2Cl 7- in small amounts. The calculated transport properties (diffusion coefficients, electrical conductivity and viscosity) of EMI-AlCl4 are in good agreement with experimental data.

Published
2016
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4. Epitaxial Synthesis of Blue Phosphorene

Author

Hamid Oughaddou, Abdelkader Kara, Ari P. Seitsonen, Andrew J. Mayne, Gérald Dujardin, Hanna Enriquez, Azzedine Bendounan, Yongfeng Tong, Wei Zhang, China Aerospace Science and Industry Corporation (CASIC), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), University of Central Florida [Orlando] (UCF), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire de Photophysique Moléculaire (PPM), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires d’Orsay (ISMO), CNRS, Université Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France, TEMPO Beamline, Synchrotron SOLEIL L’Orme des Merisiers Saint-Aubin B.P.48, Gif-sur-Yvette F-91192, Physics Department, University of Central Florida, and Département de Chimie, École Normale Supérieure

Subjects
Electron mobility, 82D80, Materials science, Photoemission spectroscopy, Band gap, FOS: Physical sciences, 02 engineering and technology, 010402 general chemistry, Epitaxy, 01 natural sciences, Biomaterials, chemistry.chemical_compound, Monolayer, General Materials Science, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], Condensed Matter - Materials Science, business.industry, Materials Science (cond-mat.mtrl-sci), General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Phosphorene, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Direct and indirect band gaps, 0210 nano-technology, business, Biotechnology, Molecular beam epitaxy
Abstract

Phosphorene is a new two-dimensional material composed of a single or few atomic layers of black phosphorus. Phosphorene has both an intrinsic tunable direct band gap and high carrier mobility values, which make it suitable for a large variety of optical and electronic devices. However, the synthesis of single-layer phosphorene is a major challenge. The standard procedure to obtain phosphorene is by exfoliation. More recently, the epitaxial growth of single-layer phosphorene on Au(111) has been investigated by molecular beam epitaxy and the obtained structure has been described as a blue-phosphorene sheet. In the present study, large areas of high-quality monolayer phosphorene, with a band gap value at least equal to 0.8 eV, have been synthesized on Au(111). Our experimental investigations, coupled with DFT calculations, give evidence of two distinct phases of blue phosphorene on Au(111), instead of one as previously reported, and their atomic structures have been determined., Comment: This paper reports on the epitaxial synthesis of blue phosphorene

Published
2018
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5. Ultra-broadband 2D electronic spectroscopy of carotenoid-bacteriochlorophyll interactions in the LH1 complex of a purple bacterium

Author

Giulio Cerullo, Dario Polli, Richard J. Cogdell, Larry Lüer, Marco Garavelli, Anne-Marie Carey, Margherita Maiuri, Kirsty Hacking, Julien Réhault, Apoptose, cancer et immunité (U848), Université Paris-Sud - Paris 11 (UP11)-Institut Gustave Roussy (IGR)-Institut National de la Santé et de la Recherche Médicale (INSERM), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Mathematics Sciences Institute (MSI, ANU), Australian National University (ANU), Laboratoire de Chimie - UMR5182 (LC), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Molecular Cell and System Biology, University of Glasgow, Politecnico di Milano [Milan] (POLIMI), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Gustave Roussy (IGR)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Maiuri, M., Rehault, J., Carey, A.-M., Hacking, K., Garavelli, M., Luer, L., Polli, D., Cogdell, R.J., and Cerullo, G.

Subjects
RAMAN EXCITATION PROFILES, PHOTOSYNTHETIC BACTERIA, Analytical chemistry, Light-Harvesting Protein Complexes, General Physics and Astronomy, Infrared spectroscopy, 02 engineering and technology, 010402 general chemistry, Rhodospirillum rubrum, 01 natural sciences, 7. Clean energy, Molecular physics, Electron spectroscopy, 2-DIMENSIONAL FEMTOSECOND SPECTROSCOPY, Light-harvesting complex, chemistry.chemical_compound, Physics and Astronomy (all), IR SPECTROSCOPY, Physical and Theoretical Chemistry, Bacteriochlorophylls, LIGHT-HARVESTING COMPLEX, ComputingMilieux_MISCELLANEOUS, biology, Chemistry, Spectrum Analysis, 021001 nanoscience & nanotechnology, biology.organism_classification, Internal conversion (chemistry), Carotenoids, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, FOURIER-TRANSFORM SPECTROSCOPY, EXCITED-STATES, 1(1)B(U)(-) STATE, STARK SPECTROSCOPY, Excited state, Photosynthetic bacteria, Bacteriochlorophyll, ENERGY-TRANSFER, 0210 nano-technology
Abstract

We investigate the excitation energy transfer (EET) pathways in the photosynthetic light harvesting 1 (LH1) complex of purple bacterium Rhodospirillum rubrum with ultra-broadband two-dimensional electronic spectroscopy (2DES). We employ a 2DES apparatus in the partially collinear geometry, using a passive birefringent interferometer to generate the phase-locked pump pulse pair. This scheme easily lends itself to two-color operation, by coupling a sub-10 fs visible pulse with a sub-15-fs near-infrared pulse. This unique pulse combination allows us to simultaneously track with extremely high temporal resolution both the dynamics of the photoexcited carotenoid spirilloxanthin (Spx) in the visible range and the EET between the Spx and the B890 bacterio-chlorophyll (BChl), whose Qx and Qy transitions peak at 585 and 881 nm, respectively, in the near-infrared. Global analysis of the one-color and two-color 2DES maps unravels different relaxation mechanisms in the LH1 complex: (i) the initial events of the internal conversion process within the Spx, (ii) the parallel EET from the first bright state S2 of the Spx towards the Qx state of the B890, and (iii) the internal conversion from Qx to Qy within the B890.

Published
2015
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6. Multiset multivariate curve resolution of transient absorption spectroscopy data to model ultrafast photodynamics

Author

Debus, B., Devos, O., Orio, M., Réhault, J., Burdzinski, G., Ruckebusch, C., Sliwa, M., Institute of Chemistry, St Petersburg State University (SPbU), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Faculty of Physics, Adam Mickiewicz University in Poznań (UAM), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Published
2015

7. Time-Resolved Visible and Infrared Study of the Cyano Complexes of Myoglobin and of Hemoglobin I from Lucina pectinata

Author

Carlos Ruiz, Luigi Bonacina, Frank van Mourik, Frédéric Chaussard, Ruth Pietri, Majed Chergui, Peter Hamm, Jan Helbing, Alejandro Gonzalez-Gonzalez, Jens Bredenbeck, Cacimar Ramos-Alvarez, Juan López-Garriga, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire de Spectroscopie Ultrarapide, Ecole Polytechnique Fédérale de Lausanne (EPFL), Department of Chemistry, University of Puerto Rico at Mayagüez (UPR-M), and Laboratoire de spectroscopie ultrarapide

Subjects
DYNAMICS, Time Factors, Hemeprotein, Spectrophotometry, Infrared, Ultraviolet Rays, Infrared, Iron, Population, Biophysics, Analytical chemistry, Electrons, Heme, 02 engineering and technology, 010402 general chemistry, Photochemistry, 01 natural sciences, CARBONMONOXY MYOGLOBIN, Hemoglobins, chemistry.chemical_compound, BINDING, Spectroscopy, Fourier Transform Infrared, Ultrafast laser spectroscopy, ABSORPTION, Animals, Horses, Muscle, Skeletal, Spectroscopy, education, Absorption (electromagnetic radiation), VIBRATIONAL-ENERGY RELAXATION, HEME-PROTEINS, Photobiophysics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], education.field_of_study, Myoglobin, Chemistry, Lasers, DOCKING SITE, PHOTODISSOCIATION, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Kinetics, RESOLUTION, Mollusca, Spectrophotometry, 0210 nano-technology, RESONANCE RAMAN-SPECTROSCOPY
Abstract

International audience; The dynamics of the ferric CN complexes of the heme proteins Myoglobin and Hemoglobin I from the clam Lucina pectinata upon Soret band excitation is monitored using infrared and broad band visible pump-probe spectroscopy. The transient response in the UV-vis spectral region does not depend on the heme pocket environment and is very similar to that known for ferrous proteins. The main feature is an instantaneous, broad, short-lived absorption signal that develops into a narrower red-shifted Soret band. Significant transient absorption is also observed in the 360 - 390 nm range. At all probe wavelengths the signal decays to zero with a longest time constant of 3.6 ps. The infrared data on MbCN reveal a bleaching of the C = N stretch vibration of the heme-bound ligand, and the formation of a five-times weaker transient absorption band, 28 cm(-1) lower in energy, within the time resolution of the experiment. The MbC = N stretch vibration provides a direct measure for the return of population to the ligated electronic ( and vibrational) ground state with a 3 - 4 ps time constant. In addition, the CN-stretch frequency is sensitive to the excitation of low frequency heme modes, and yields independent information about vibrational cooling, which occurs on the same timescale.

Published
2004
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8. First-principles and experimental NMR study of sodium silicate glasses

Author

Thibault Charpentier, Filipe Vasconcelos, Mathieu Salanne, Olivier Villain, Ari Seitsonen, Frederic Angeli, Sophie SCHULLER, Laboratoire Structure et Dynamique par Résonance Magnétique (LCF) (LSDRM), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), 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-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-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-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physicochimie des Electrolytes, Colloïdes et Sciences Analytiques (PECSA), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Département de recherche sur les technologies pour l'enrichissement, le démantèlement et les déchets (DE2D), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Département de recherche sur les Procédés et Matériaux pour les Environnements complexes (DPME)

Subjects
[CHIM.MATE]Chemical Sciences/Material chemistry, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2014

9. Nano-confinement of radical interaction to tailor fast switching photochromic materials

Author

Sliwa, M., Debus, B., Hatano, S., Katayama, T., Vitale, R., Orio, M., Choël, M., Piard Jonathan, Métivier, R., Réhault, J., Ruckebusch, C., Nakatani, K., Abe, J., Miyasaka, H., Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, School of Science and Engineering, Aoyama Gakuin University (AGU), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University [Osaka], and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Published
2013

10. Synthesis, single particle and ultrafast spectroscopy of new photo-active organic nanoparticles

Author

Sliwa, M., Debus, B., Ruckebusch, C., Burdzinski, G., Asahi, T., Hofkens, J., Helbing, J., Miyasaka, H., Abe, J., Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Quantum Electronics Laboratory, Adam Mickiewicz University in Poznań (UAM), Department of Applied Physics, Osaka University [Osaka], Department of Chemistry and Institute for Nanoscale Physics and chemistry (INPAC), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Chemistry, Graduate School of Science, Tohoku University [Sendai], CREST, Japan Science and Technology Agency (JST), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Published
2013

11. Mechanistic aspects of ketene formation deduced from femtosecond photolysis of diazocyclohexadienone, o-phenylene thioxocarbonate, and 2-chlorophenol

Author

Michel Sliwa, Jacek Kubicki, Christopher M. Hadad, Gotard Burdzinski, Hoi Ling Luk, Shubham Vyas, Matthew S. Platz, Julien Réhault, Yunlong Zhang, Quantum Electronics Laboratory, Adam Mickiewicz University in Poznań (UAM), Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Chemistry & Biochemistry, Ohio State University [Columbus] (OSU), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
010405 organic chemistry, Chemistry, Organic Chemistry, Ketene, Wolff rearrangement, 010402 general chemistry, Photochemistry, 01 natural sciences, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Cyclopentadienyl complex, Absorption band, Excited state, Ultrafast laser spectroscopy, Singlet state, Carbene
Abstract

The photochemistry of diazocyclohexadienone (1), o-phenylene thioxocarbonate (2), and 2-chlorophenol (3) in solution was studied using time-resolved UV-vis and IR transient absorption spectroscopies. In these three cases, the same product cyclopentadienyl ketene (5) is formed, and two different mechanistic pathways leading to this product are discussed: (a) rearrangement in the excited state (RIES) and (b) a stepwise route involving the intermediacy of vibrationally excited or relaxed carbene. Femtosecond UV-vis detection allows observation of an absorption band assigned to singlet 2-oxocyclohexa-3,5-dienylidene (4), and this absorption feature decays with an 30 ps time constant in hexane and acetonitrile. The excess vibrational energy present in nascent carbenes results in the ultrafast Wolff rearrangement of the hot species. IR detection shows that photoexcited o-phenylene thioxocarbonate (2) and 2-chlorophenol (3) efficiently form the carbene species while diazocyclohexadienone (1) photochemistry proceeds mainly by a concerted process.

Published
2013
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12. Silver in geological fluids from in situ X-ray absorption spectroscopy and first-principles molecular dynamics

Author

Gleb S. Pokrovski, G. Ferlat, Romain Jonchiere, Jean-Louis Hazemann, Jacques Roux, Rodolphe Vuilleumier, Ari P. Seitsonen, Géosciences Environnement Toulouse (GET), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (NEEL - MRS), Institut Néel (NEEL), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Matériaux, Rayonnements, Structure (MRS), University of Zurich, and Pokrovski, Gleb S

Subjects
10120 Department of Chemistry, X-ray absorption spectroscopy, Aqueous solution, 010504 meteorology & atmospheric sciences, Absorption spectroscopy, Extended X-ray absorption fine structure, Chemistry, Analytical chemistry, 010502 geochemistry & geophysics, 01 natural sciences, Chloride, XANES, Absorption edge, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], 13. Climate action, Geochemistry and Petrology, 540 Chemistry, medicine, 1906 Geochemistry and Petrology, Solubility, 0105 earth and related environmental sciences, medicine.drug
Abstract

The molecular structure and stability of species formed by silver in aqueous saline solutions typical of hydrothermal settings were quantified using in situ X-ray absorption spectroscopy (XAS) measurements, quantum-chemical modeling of near-edge absorption spectra (XANES) and extended fine structure spectra (EXAFS), and first-principles molecular dynamics (FPMD). Results show that in nitrate-bearing acidic solutions to at least 200 °C, silver speciation is dominated by the hydrated Ag + cation surrounded by 4–6 water molecules in its nearest coordination shell with mean Ag–O distances of 2.32 ± 0.02 A. In NaCl-bearing acidic aqueous solutions of total Cl concentration from 0.7 to 5.9 mol/kg H 2 O ( m ) at temperatures from 200 to 450 °C and pressures to 750 bar, the dominant species are the di-chloride complex AgCl 2 − with Ag–Cl distances of 2.40 ± 0.02 A and Cl–Ag–Cl angle of 160 ± 10°, and the tri-chloride complex AgCl 3 2− of a triangular structure and mean Ag–Cl distances of 2.60 ± 0.05 A. With increasing temperature, the contribution of the tri-chloride species decreases from ∼50% of total dissolved Ag in the most concentrated solution (5.9 m Cl) at 200 °C to less than 10–20% at supercritical temperatures for all investigated solutions, so that AgCl 2 − becomes by far the dominant Ag-bearing species at conditions typical of hydrothermal–magmatic fluids. Both di- and tri-chloride species exhibit outer-sphere interactions with the solvent as shown by the detection, using FPMD modeling, of H 2 O, Cl − , and Na + at distances of 3–4 A from the silver atom. The species fractions derived from XAS and FPMD analyses, and total AgCl (s) solubilities, measured in situ in this work from the absorption edge height of XAS spectra, are in accord with thermodynamic predictions using the stability constants of AgCl 2 − and AgCl 3 2− from Akinfiev and Zotov (2001) and Zotov et al. (1995) , respectively, which are based on extensive previous AgCl (s) solubility measurements. These data are thus recommended for chemical equilibrium calculations in mineral–fluid systems above 200 °C. In contrast, our data disagree with SUPCRT-based datasets for Ag–Cl species, which predict large fractions of high-order chloride species, AgCl 3 2− and AgCl 4 3− in high-temperature saline fluids. Comparisons of the structural and stability data of Ag–Cl species derived in this study with those of their Au and Cu analogs suggest that molecular-level differences amongst the chloride complexes such as geometry, dipole moment, distances, and resulting outer-sphere interactions with the solvent may account, at least partly, for the observed partitioning of Au, Ag and Cu in vapor–brine and fluid–melt systems. In hydrothermal environments dominated by fluid–rock interactions, the contrasting affinity of these metals for sulfur ligands and the differences both in chemistry and stability of their main solid phases (Ag sulfides, Cu–Fe sulfides, and native Au) largely control the concentration and distribution of these metals in their economic deposits.

Published
2013
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13. Synthesis and ultrafast spectroscopy of fast Hexaarylbiimidazole nanoparticles: radical interaction as a sensitive probe of structural change?

Author

Debus, B., Hatano, S., Vitale, R., Ruckebusch, C., Metivier, R., Nakatani, K., Rehault, J., Helbing, J., Miyasaka, H., Abe, J., Sliwa, M., Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Chemistry, Graduate School of Science, Tohoku University [Sendai], Department of Chemistry, Aoyama Gakuin University (AGU), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Published
2012

14. Synthèse et études spectroscopiques de nanoparticules photochromes à base de fast hexaarylbiimidazole

Author

Sliwa, M., Debus, B., Vittale, R., Ruckebusch, C., Orio, M., Vezin, H., Delbaere, S., Nakatani, K., Helbing, J., Miyasaka, H., Abe, J., Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Department of Chemistry, Graduate School of Science, Tohoku University [Sendai], Department of Chemistry, Aoyama Gakuin University (AGU), and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry
Published
2012

15. Activation of aliphatic C-H bonds by tetracyanobenzene photosensitization. A time-resolved and steady-state investigation

Author

Protti, Stefano, Fagnoni, Maurizio, Monti, Sandra, Rehault, Julien, Poizat, Olivier, Albini, Angelo, PhotoGreen Lab, Department of Chemistry, University of Pavia, Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Istituto per la Sintesi Organica e la Fotoreattività (ISOF-CNR), Consiglio Nazionale delle Ricerche (CNR), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Università degli Studi di Pavia = University of Pavia (UNIPV), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
Cyclohexane, 010405 organic chemistry, General Chemical Engineering, Radical, General Chemistry, 010402 general chemistry, Photochemistry, 01 natural sciences, Chemical reaction, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Electron transfer, Radical ion, chemistry, Flash photolysis, Molecule, Triethylamine
Abstract

The photochemistry of 1,2,4,5-tetracyanobenzene (TCB) in acetonitrile in the presence of representative aliphatic donors (cyclohexane, 1,4-dioxane and triethylamine) has been investigated by femtosecond (fs) and nanoseconds (ns) flash photolysis as well as steady state irradiation in order to define the kinetic frame for the activation of aliphatic C-H bonds. Unlike in the case of aromatics, no ground state complex (except possibly in the case of triethylamine) or exciplex is formed. The lowest excited singlet is quenched and forms the free radical ions. The efficiency of the process, measured by the yield of TCB˙− (0.84 with cyclohexane, 0.15 with 1,4-dioxane, 0.37 with triethylamine) depends on the rate of return electron transfer, low for a high exothermicity. The chemical reaction following the electron transfer step depends on the properties of the radical cation. Thus, with cyclohexane deprotonation is slow and does not occur measurably on a microsecond scale, while on a longer time scale, the formation of alkyl radicals competes with back electron transfer between the free ions. The deprotonation of amine radical cations is faster and the resulting α-aminoalkyl radicals reduce a further molecule of TCB, causing the accumulation of the radical anion which is indefinitely stable in the absence of oxygen.

Published
2012
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16. Van der Waals effects in ab initio water at ambient and supercritical conditions

Author

Ari P. Seitsonen, A. Marco Saitta, G. Ferlat, Romain Jonchiere, Rodolphe Vuilleumier, Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Zurich, Ferlat, G, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)

Subjects
10120 Department of Chemistry, Diffusion and thermal diffusion, Van der Waals surface, Ab initio, General Physics and Astronomy, Thermodynamics, 61.20.Ne, 61.20.Ja, Molecular Dynamics Simulation, London dispersion force, Structure of simple liquids, symbols.namesake, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Computational chemistry, 540 Chemistry, Van der Waals radius, Physical and Theoretical Chemistry, 66.10.C, density functional theory, Chemistry, ab initio calculations, diffusion, Water, Hydrogen Bonding, Computer simulation of liquid structure, 3100 General Physics and Astronomy, Supercritical fluid, Theorem of corresponding states, Models, Chemical, [SDU]Sciences of the Universe [physics], symbols, van der Waals forces, Quantum Theory, Density functional theory, van der Waals force, liquid structure, 1606 Physical and Theoretical Chemistry, Reactive Oxygen Species
Abstract

International audience; Density functional theory (DFT) within the generalized gradient approximation (GGA) is known to poorly reproduce the experimental properties of liquid water. The poor description of the dispersion forces in the exchange correlation functionals is one of the possible causes. Recent studies have demonstrated an improvement in the simulated properties when they are taken into account. We present here a study of the effects on liquid water of the recently proposed semi-empirical correction of Grimme et al. [J. Chem. Phys. 132, 154104 (2010)]. The difference between standard and corrected DFT-GGA simulations is rationalized with a detailed analysis upon modifying an accurate parameterised potential. This allows an estimate of the typical range of dispersion forces in water. We also show that the structure and diffusivity of ambient-like liquid water are sensitive to the fifth neighbor position, thus highlighting the key role played by this neighbor. Our study is extended to water at supercritical conditions, where experimental and theoretical results are much more scarce. We show that the semi-empirical correction by Grimme et al. improves significantly, although somewhat counter-intuitively, both the structural and the dynamical description of supercritical water.

Published
2011
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17. Vibrational Self-Trapping in an α-Helix

Author

Julian Edler, Vincent Pouthier, Rolf Pfister, Peter Hamm, Cyril Falvo, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire de physique moléculaire, Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)

Subjects
[PHYS]Physics [physics], Materials science, Infrared, Exciton, Trapping, Pump probe, 010402 general chemistry, 01 natural sciences, Molecular physics, Hot band, 3. Good health, 0104 chemical sciences, 0103 physical sciences, Helix, Excited state absorption, 010306 general physics, ComputingMilieux_MISCELLANEOUS
Abstract

Infrared pump probe experiments on the NH mode of an α-helix reveal two excited State absorption signals, which are an explicit indication of self-localized vibrational excitons.

Published
2005
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18. Direct Observation of Self-Trapped Vibrational States inα-Helices

Author

Cyril Falvo, Peter Hamm, Vincent Pouthier, Julian Edler, Rolf Pfister, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire de physique moléculaire, Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)

Subjects
Models, Molecular, Spectrophotometry, Infrared, Absorption spectroscopy, Nitrogen, Phonon, General Physics and Astronomy, 02 engineering and technology, Polaron, Vibration, 01 natural sciences, Molecular physics, Protein Structure, Secondary, Nuclear magnetic resonance, 0103 physical sciences, Bound state, Computer Simulation, Amino Acids, 010306 general physics, Spectroscopy, ComputingMilieux_MISCELLANEOUS, [PHYS]Physics [physics], Physics, Quantitative Biology::Biomolecules, Hydrogen Bonding, 021001 nanoscience & nanotechnology, 3. Good health, Models, Chemical, Polyglutamic Acid, Excited state, Helix, Fermi resonance, 0210 nano-technology
Abstract

Femtosecond infrared pump-probe spectroscopy of the N-H mode of a stable $\ensuremath{\alpha}$-helix reveals two excited-state absorption bands, which disappear upon unfolding of the helix. A quantitative comparison with polaron theory shows that these two bands reflect two types of two-vibron bound states connected to the trapping of two vibrons at the same site and at nearest neighbor sites, respectively. The latter states originate from an acoustic phonon in the helix, which correlates adjacent sites.

Published
2004
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19. STM Study of Terephthalic Acid Self-Assembly on Au(111): Hydrogen-Bonded Sheets on an Inhomogeneous Substrate †

Author

Ari P. Seitsonen, Johannes V. Barth, Harald Brune, Klaus Kern, Stéphane Pons, Sylvain Clair, Institut de Physique des Nanostructures (IPN), Ecole Polytechnique Fédérale de Lausanne (EPFL), University of Zurich, Clair, S, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Institute of Physics, Max-Planck-Institut für Festkörperforschung, and Max-Planck-Gesellschaft

Subjects
10120 Department of Chemistry, Supramolecular chemistry, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, chemistry.chemical_compound, Adsorption, Ab initio quantum chemistry methods, law, 540 Chemistry, Materials Chemistry, Molecule, Physical and Theoretical Chemistry, 2505 Materials Chemistry, ComputingMilieux_MISCELLANEOUS, Terephthalic acid, Hydrogen bond, 2508 Surfaces, Coatings and Films, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Surfaces, Coatings and Films, Crystallography, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Self-assembly, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Scanning tunneling microscope, 1606 Physical and Theoretical Chemistry, 0210 nano-technology
Abstract

The adsorption and ordering of the molecule terephthalic acid (TPA), 1,4-benzene-dicarboxylic acid C6H4-(COOH)(2), on the reconstructed Au(111) surface has been studied in situ in ultrahigh vacuum by scanning tunneling microscopy (STM) at room temperature. Two-dimensional (2D) self-assembled supramolecular domains evolve, wherein the well-known one-dimensional (1D) carboxyl H-bond pairing scheme is identified. Since the individual molecules occupy a distinct adsorption site and the supramolecular ordering usually extends over several substrate reconstruction domains, a significant variation in hydrogen bond lengths is encountered, which illustrates the versatility of hydrogen bridges in molecular engineering at surfaces. Ab initio calculations for a 1D H-bonded molecular chain provide insight into the limited geometric response of the molecules in different local environments.

Published
2004
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20. Ultrafast Carotenoid to Retinal Energy Transfer in Xanthorhodopsin Revealed by the Combination of Transient Absorption and Two‐Dimensional Electronic Spectroscopy

Author

Simone Taioli, Itay Gdor, Julien Emile Réhault, Sanford Ruhman, Giulio Cerullo, Ivan Rivalta, Noga Friedman, Francesco Segatta, Mordechai Sheves, Marco Garavelli, Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Politecnico di Milano [Milan] (POLIMI), Dipartimento di Chimica 'G. Ciamician', Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Segatta, Gdor Itay, Rehault Julien, Taioli Simone, Friedman Noga, Sheves Mordechai, Rivalta Ivan, Ruhman Sanford, Cerullo Giulio, Garavelli Marco

Subjects
530 Physics, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Signal, Electron spectroscopy, Catalysis, chemistry.chemical_compound, Ultrafast laser spectroscopy, 540 Chemistry, ComputingMilieux_MISCELLANEOUS, Chemistry, Organic Chemistry, Chemistry (all), Retinal, General Chemistry, Chromophore, 021001 nanoscience & nanotechnology, carotenoid, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, electronic spectroscopy, Amplitude, Chemical physics, retinal protein, 570 Life sciences, biology, 0210 nano-technology, Ground state, Förster energy transfer, Ultrashort pulse, ground state vibration
Abstract

By comparing two-dimensional electronic spectroscopy (2DES) and Pump-Probe (PP) measurements on xanthorhodopsin (XR) and reduced-xanthorhodopsin (RXR) complexes, the ultrafast carotenoid-to-retinal energy transfer pathway is revealed, at very early times, by an excess of signal amplitude at the associated cross-peak and by the carotenoid bleaching reduction due to its ground state recovery. The combination of the measured 2DES and PP spectroscopic data with theoretical modelling allows a clear identification of the main experimental signals and a comprehensive interpretation of their origin and dynamics. The remarkable velocity of the energy transfer, despite the non-negligible energy separation between the two chromophores, and the analysis of the underlying transport mechanism, highlight the role played by the ground state carotenoid vibrations in assisting the process.

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21. Synthesis and ultrafast spectroscopy of photochromic nanoparticles with fast thermal back reaction

Author

Sliwa, M., Debus, B., Hatano, S., Katayama, T., Vitale, R., Orio, M., Choël, M., Piard Jonathan, Métivier, R., Réhault, J., Ruckebusch, C., Nakatani, K., Abe, J., Miyasaka, H., Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE), Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Centrale Lille Institut (CLIL), Department of Chemistry, School of Science and Engineering, Aoyama Gakuin University (AGU), Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires (PPSM), École normale supérieure - Cachan (ENS Cachan)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Physikalisch-Chemisches Institut [Zürich], Universität Zürich [Zürich] = University of Zurich (UZH), Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University [Osaka], and Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry

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