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23 results on '"Marie-Catherine Heitz"'

1. Dihydropyrene/Cyclophanediene Photoswitching Mechanism Revisited with Spin-Flip Time-Dependent Density Functional Theory: Nature of the Photoisomerization Funnel at Stake!

Author

Elise Lognon, Rudraditya Sarkar, Marie-Catherine Heitz, Martial Boggio-Pasqua, Photochimie théorique et computationnelle (LCPQ) (PTC), Laboratoire de Chimie et Physique Quantiques Laboratoire (LCPQ), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona (IQCC), and Universitat de Girona (UdG)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Physical and Theoretical Chemistry
Abstract

International audience; The complex photoisomerization mechanism of the dihydropyrene (DHP) photochromic system is revisited using spin-flip time-dependent density functional theory (SF-TD-DFT). The photoinduced ring-opening reaction of DHP into its cyclophanediene isomer involves multiple coupled electronic states of different character. A balanced treatment of both static and dynamic electron correlations is required to determine both the photophysical and photochemical paths in this system. The present results provide a refinement of the mechanistic picture provided in a previous complete active space self-consistent field plus second-order perturbation theory (CASPT2//CASSCF) study based on geometry optimizations at the CASSCF level. In particular, the nature of the conical intersection playing the central role of the photochemical funnel is different. While at the CASSCF level, the crossing with the ground state involves a covalent doubly excited state leading to a three-electron/three-center bond conical intersection, SF-TD-DFT predicts a crossing between the ground state and a zwitterionic state. These results are supported by multi-state CASPT2 calculations. This study illustrates the importance of optimizing conical intersections at a sufficiently correlated level of theory to describe a photochemical path involving crossings between covalent and ionic states.

Published
2023

2. Absorption band structure of the photochromic dimethyldihydropyrene/metacyclophanediene couple. Insight from vibronic coupling theory

Author

Rudraditya Sarkar, Marie-Catherine Heitz, Martial Boggio-Pasqua, Photochimie théorique et computationnelle (LCPQ) (PTC), Laboratoire de Chimie et Physique Quantiques Laboratoire (LCPQ), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche « Matière et interactions » (FeRMI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Institut de Química Computacional i Catàlisi and Departament de Química, Universitat de Girona (IQCC), Universitat de Girona (UdG), ANR-17-EURE-0009,NanoX,Science et Ingénierie à l'Echelle Nano(2017), and ANR-18-CE29-0012,Photochromics,Architectures Moléculaires Multi-Photochromes Innovantes pour la Production de NO et 1O2(2018)

Subjects
[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, General Physics and Astronomy, Physical and Theoretical Chemistry
Abstract

International audience; A detailed insight behind the structure of absorption bands of the photochromic couple dimethyldihydropyrene (DHP)/metacyclophanediene (CPD) is studied employing vibronic coupling theory. Two separate model molecular Hamiltonians, including a maximum of four electronic states and 18 vibrational modes for DHP and five electronic states and 20 vibrational modes for CPD, are constructed in a diabatic electronic representation. The parameters of the Hamiltonians are estimated from the electronic energies obtained from extensive density functional theory (DFT) and time-dependent DFT calculations. Based on these Hamiltonians’ parameters, a detailed analysis of potential energy curves is performed in conjunction with positional and energetic locations of several stationary points in multi-dimensional potential energy surfaces. Based on the results of electronic structure calculations, quantum nuclear dynamics studies on the electronic excited states of DHP and CPD are performed to understand the impact of non-adiabatic effects on the formation of vibronic structures of absorption bands of these photo-isomers.

Published
2022

3. Electronic Excited States and UV–Vis Absorption Spectra of the Dihydropyrene/Cyclophanediene Photochromic Couple: a Theoretical Investigation

Author

Guy Royal, Marie-Catherine Heitz, Martial Boggio-Pasqua, Rudraditya Sarkar, Photochimie théorique et computationnelle (LCPQ) (PTC), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Département de Chimie Moléculaire (DCM), Université Grenoble Alpes (UGA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)

Subjects
010304 chemical physics, Absorption spectroscopy, Electronic correlation, Chemistry, Electronic structure, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Molecular physics, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Photochromism, Atomic electron transition, Excited state, 0103 physical sciences, Density functional theory, Physical and Theoretical Chemistry, Absorption (electromagnetic radiation)
Abstract

Dihydropyrene (DHP)/cyclophanediene (CPD) is a fascinating photoswitchable organic system displaying negative photochromism. Upon irradiation in the visible region, the colored DHP can be converted to its open-ring CPD colorless isomer, which can be converted back to DHP by UV light. DHP and CPD thus possess very different absorption spectra whose absorption bands have never been assigned in detail so far. In this work, we characterize the vertical electronic transitions of the first six and seven excited states of DHP and CPD, respectively, aiming for a realistic comparison with experiment. We used state-of-the-art electronic structure methods [e.g., complete active space second-order perturbation theory (CASPT2), n-electron valence-state perturbation theory (NEVPT2), extended multiconfigurational quasi-degenerate perturbation theory (XMCQDPT2), and third-order algebraic diagrammatic construction ADC(3)] capable of describing differential electron correlation. Vertical transition energies were also computed with time-dependent density functional theory (TD-DFT) and compared to these accurate methods. After the reliability of TD-DFT was validated for the main optical transitions, this efficient method was used to simulate the absorption spectra of DHP and CPD in the framework of the Franck-Condon Herzberg-Teller approximation and also using the nuclear ensemble approach. Overall, for both methods, the simulated absorption spectra reproduce nicely the main spectral features of the DHP and CPD isomers, that is, the main four absorption bands of increasing intensity of DHP and the absorption rise below 300 nm for CPD.

Published
2020

4. Ultrafast chiroptical switching in UV-excited molecules

Author

Vincent Wanie, Etienne Bloch, Erik P. Månsson, Lorenzo Colaizzi, Krishna Saraswathula, Sergey Ryabchuk, François Légaré, Andrea Trabattoni, Valérie Blanchet, Marie-Catherine Heitz, Nadia Ben Amor, Yann Mairesse, Bernard Pons, and Francesca Calegari

Abstract

A novel light source delivering few-cycle UV pulses is used to reveal an ultrafast modulation of the chiroptical properties of photoexcited chiral molecules, probed by time-resolved photoelectron circular dichroism. We report a periodic inversion of photoelectron emission direction in methyl-lactate on a timescale as short as 6fs.

Published
2022

5. Femtosecond-resolved Rydberg states dynamics in chiral molecules

Author

Bernard Pons, Etienne Bloch, Lorenzo Colaizzi, Andrea Trabattoni, Krishna Saraswathula, Erik P. Månsson, Francesca Calegari, François Légaré, Marie-Catherine Heitz, Sergey Riabchuk, Valérie Blanchet, Nadia Ben Amor, Yann Mairesse, and Vincent Wanie

Subjects
Physics, Attosecond, Photodissociation, medicine.disease_cause, Molecular dynamics, symbols.namesake, Chemical physics, Femtosecond, medicine, Rydberg formula, symbols, Spectroscopy, Ultrashort pulse, Ultraviolet
Abstract

As an important branch of molecular science, time-resolved ultraviolet (UV) spectroscopy promises to address ultrafast photochemical and photobiological processes that play key roles in nature, from ozone photolysis to UV-induced DNA damage [1] , [2] . At the few-femtosecond and attosecond timescales, the study of UV-induced molecular dynamics has been hampered due to the technical challenges for the generation and manipulation of ultrabroadband, few-cycle UV pulses [3] – [5] .

Published
2021

6. Dependency of the Dimethyldihydropyrene Photochromic Properties on the Number of Pyridinium Electron‐Withdrawing Groups

Author

Elise Lognon, Frédérique Loiseau, Eric Saint-Aman, Assil Bakkar, Martial Boggio-Pasqua, Marie-Catherine Heitz, Saioa Cobo, Guy Royal, Photochimie théorique et computationnelle (LCPQ) (PTC), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Département de Chimie Moléculaire (DCM), Université Grenoble Alpes (UGA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)

Subjects
Quantum yield, 02 engineering and technology, Hardware_PERFORMANCEANDRELIABILITY, Conical intersection, 010402 general chemistry, 021001 nanoscience & nanotechnology, Photochemistry, 01 natural sciences, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, 3. Good health, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Photochromism, chemistry, Excited state, Polar effect, Hardware_INTEGRATEDCIRCUITS, Pyridinium, Physical and Theoretical Chemistry, 0210 nano-technology, Isomerization, Topology (chemistry)
Abstract

Photochromic dimethyldihydropyrenes substituted with electron-withdrawing pyridinium groups have shown an increase of photo-induced ring-opening efficiency and a light sensitivity that is red shifted relative to the unsubstituted compound. However, a recently synthesized tetrapyridinium derivative showed a considerable decrease of the photo-isomerization quantum yield relative to the monopyridinium and bispyridinium derivatives. We provide a rationale for this unexpected photochemical behavior based on the comparative theoretical investigations of the relevant excited states of these systems. In particular, we found that the nature and order of the lowest two excited states depend on the number of pyridinium groups and on the symmetry of the system. While the lowest S1 excited state is photo-active in the monopyridinium and bispyridinium derivatives, the photo-isomerizing state is S2 in the reference unsubstituted compound and both S1 and S2 lead to isomerization in the tetrapyridinium derivative, albeit with a low efficiency. In the latter derivative, the photo-isomerization is hindered by the particular S1 /S2 conical intersection topology.

Published
2020

7. RASPT2 study of the valence excited states of an iron–porphyrin–carbonyl model complex

Author

Nadia Ben Amor, Marie-Catherine Heitz, Groupe Méthodes et outils de la chimie quantique (LCPQ) (GMO), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Photochimie théorique et computationnelle (LCPQ) (PTC), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3)

Subjects
Physics, Valence (chemistry), 010304 chemical physics, General Chemistry, 010402 general chemistry, 01 natural sciences, Molecular physics, Porphyrin, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Computational Mathematics, chemistry.chemical_compound, Q band, Atomic orbital, chemistry, Excited state, 0103 physical sciences, Singlet state, Ionization energy, Wave function, ComputingMilieux_MISCELLANEOUS
Abstract

Multireference wavefunction calculations of the singlet valence excited states of an iron-porphyrin-pyrazine-carbonyl complex up to the Soret band (about 3 eV) are presented. This complex is chosen to be a model for the active site of carboxyhemoglobin/carboxymyoglobin. The investigations are performed at the restricted active space second-order perturbation (RASPT2) level involving an extended active space on the porphyrin ligand in addition to the active orbitals needed for the description of the metal-ligand interactions. Metal-to-ligand-charge-transfer states d → π* and some metal-centered d → d transitions are found in the lowest part of the spectrum, below the first π → π* intraporphyrin transitions (Q band). Doubly excited states involving simultaneous intraporphyrin and metal-centered excitations are found in the vicinity of the second set of intraporphyrin transitions (the so-called Soret band). The effect of the extension of the active space on the porphyrin ligand beyond the Gouterman's orbitals set is investigated together with the effect of inclusion of the ionization potential electron affinity shift in the RASPT2 treatment. © 2019 Wiley Periodicals, Inc.

Published
2019

8. Methodological CASPT2 study of the valence excited states of an iron-porphyrin complex

Author

Marie-Catherine Heitz, Nadia Ben Amor, Adrien Soupart, Groupe Méthodes et outils de la chimie quantique (LCPQ) (GMO), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Photochimie théorique et computationnelle (LCPQ) (PTC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)

Subjects
010402 general chemistry, 01 natural sciences, Catalysis, Inorganic Chemistry, chemistry.chemical_compound, Ionization, 0103 physical sciences, Singlet state, Complete active space, Physical and Theoretical Chemistry, ComputingMilieux_MISCELLANEOUS, Physics::Biological Physics, Valence (chemistry), 010304 chemical physics, biology, Organic Chemistry, Active site, Porphyrin, 0104 chemical sciences, Computer Science Applications, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Computational Theory and Mathematics, chemistry, Myoglobin, Excited state, biology.protein, Atomic physics
Abstract

The singlet valence excited states of an iron-porphyrin-pyrazine-carbonyl complex are investigated up to the Soret band (about 3 eV) using multi-state complete active space with perturbation at the second order (MS-CASPT2). This complex is a model for the active site of carboxy-hemoglobin/myoglobin. The spectrum of the excited states is rather dense, comprising states of different nature: d→π* transitions, d→d states, π→π* excitations of the porphyrin, and doubly excited states involving simultaneous intra-porphyrin π→π* and d→d transitions. Specific features of the MS-CASPT2 method are investigated. The effect of varying the number of roots in the state average calculation is quantified as well as the consequence of targeted modifications of the active space. The effect of inclusion of standard ionization potential-electron affinity (IPEA) shift in the perturbation treatment is also investigated.

Published
2016

9. Theoretical study of the time-resolved photoelectron spectrum of Na 2 F: effects of thermal initial conditions

Author

Christoph Meier, G. Durand, Fernand Spiegelman, and Marie-Catherine Heitz

Subjects
Materials science, Photoemission spectroscopy, Optical physics, Laser, Molecular physics, Atomic and Molecular Physics, and Optics, law.invention, Nuclear magnetic resonance, law, Excited state, Femtosecond, Cluster (physics), Vibrational temperature, Excitation
Abstract

The excited state dynamics of the Na2F cluster initiated by a femtosecond laser pulse is studied considering a thermally excited initial sample. Within a pump-probe set-up, the time-dependent photoelectron spectrum is calculated, which is shown to be a sensitive tool to study intramolecular motion of the cluster. Temperature effects are taken into account through thermal averaging over the time-dependent spectra obtained from different initial vibrational states of the cluster. The nuclear motion upon laser excitation is described by full-dimensional quantum wavepacket propagation using explicit, realistic pump and probe pulses. The characteristic features of the time-resolved photoelectron spectra of the Na2F cluster, identified as due to periodic bending motion of the cluster as well as to the excitation of the stretching mode, are found to be robust against increasing vibrational temperature of the cluster beam. This finding is important for possible future experiments.

Published
2003

10. Time-resolved photoelectron spectra as probe of excited state dynamics: A full quantum study of the Na2F cluster

Author

G. Durand, Marie-Catherine Heitz, Christoph Meier, and Fernand Spiegelman

Subjects
Photoemission spectroscopy, Chemistry, Wave packet, General Physics and Astronomy, Electron, Laser, Potential energy, law.invention, Pulse (physics), Pseudopotential, law, Excited state, Physical and Theoretical Chemistry, Atomic physics
Abstract

The excited state dynamics of the Na2F cluster initiated by a femtosecond laser pulse is studied by quantum wave packet propagation within a pump–probe setup. The probe pulse is supposed to ionize the system to yield a photoelectron spectrum that depends on the time delay between the pump- and probe pulse. It is shown that the time dependence of the photoelectron spectrum is an extremely sensitive tool to study intramolecular motion of the cluster like the energy flow between different internal modes. The potential energy surfaces involved in the photoinduced process are calculated from a pseudopotential model with repulsive and Coulomb potentials for the ions and a quantum description of the excess electron via electron-Na+ and electron-F− pseudopotentials, polarization of the ionic cores as well as electron-ion correlation being added perturbatively. The nuclear motion upon laser excitation is described by full-dimensional quantum wave packet propagation using realistic laser pulse parameters. We find t...

Published
2003

11. Photodissociation and electronic spectroscopy of transition metal hydrides carbonyls: quantum chemistry and wave packet dynamics

Author

Chantal Daniel, Marie Catherine Heitz, Dominique Guillaumont, and Isabelle Cote-Bruand

Subjects
Absorption spectroscopy, Chemistry, Wave packet, Organic Chemistry, Photodissociation, Ab initio, Photochemistry, Biochemistry, Quantum chemistry, Electron spectroscopy, Inorganic Chemistry, Transition metal, Excited state, Materials Chemistry, Physical and Theoretical Chemistry
Abstract

The photodissociation mechanism of a number of transition metal carbonyl hydrides (HCo(CO) 4 , H 2 Fe(CO) 4 , HM(CO) 3 (H-DAB) with M=Mn, Re and H-DAB=1,4-diaza-1,3-butadiene) is followed in a time-dependent approach. The time scale of the primary reactions, the absorption spectra and the branching ratio of the concurrent dissociation pathways are deduced from wave packet propagations performed on two-dimensional ab initio potential energy surfaces connecting the electronic ground and excited states of the irradiated molecule to those of the primary products.

Published
2000

12. Photodissociation Dynamics of Organometallics: Quantum Simulation for the Dihydride Complex H2Fe(CO)4

Author

Marie-Catherine Heitz and Chantal Daniel

Subjects
Absorption spectroscopy, Chemistry, Wave packet, Photodissociation, Quantum simulator, General Chemistry, Photochemistry, Biochemistry, Molecular physics, Catalysis, Dissociation (chemistry), Colloid and Surface Chemistry, Excited state, Molecule, Irradiation
Abstract

The photodissociation dynamics of H2Fe(CO)4 have been studied through wave packet propagations on CASSCF/CCI potentials, calculated for the electronic ground and excited states, as a function of two coordinates qa and qb corresponding to molecular hydrogen elimination and CO dissociation, respectively. The theoretical absorption spectrum is characterized by two bands at 272 nm (36 700 cm-1) and 246 nm (40 500 cm-1) which have been assigned to the a1A1 → a1B1 and a1A1 → b1A1 transitions, respectively. The first band corresponds to the experimental maximum observed around 270 nm. A semiquantitative mechanism has been proposed for the photodissociation of the title molecule: (i) under irradiation at 254 nm, the a1B1 (3dyz → σg*) and b1A1 (3dx2-y2 → σg*) excited states will be populated; (ii) from the b1A1 state, the molecule will dissociate in a total and ultrafast (less than 40 fs) reaction toward the formation of Fe(CO)4 and molecular hydrogen; (iii) after the initial a1A1 → a1B1 transition, the reactive ...

Published
1997

13. Spin-orbit induced radiationless transitions in organometallics: Quantum simulation of the intersystem crossing processes in the photodissociation of HCo(CO)4

Author

Carl Ribbing, Chantal Daniel, and Marie-Catherine Heitz

Subjects
Intersystem crossing, Chemistry, Hydrogen bond, Excited state, Photodissociation, General Physics and Astronomy, Singlet state, Physical and Theoretical Chemistry, Atomic physics, Triplet state, Potential energy, Excitation
Abstract

A theoretical description of the “fast” (

Published
1997

14. Effect of structure and size on the excited states dynamics of CaArn clusters

Author

Jose J. Plata, Fernand Spiegelman, Marie-Catherine Heitz, Modélisation, Agrégats, Dynamique (LCPQ) (MAD), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3)

Subjects
Materials science, Argon, 010304 chemical physics, Icosahedral symmetry, Relaxation (NMR), chemistry.chemical_element, Electronic structure, 010402 general chemistry, 01 natural sciences, Atomic and Molecular Physics, and Optics, Spectral line, 0104 chemical sciences, chemistry, Atomic electron transition, Excited state, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Cluster (physics), Atomic physics
Abstract

This article is part of Topical issue: ISSPIC 16 - 16th International Symposium on Small Particles and Inorganic Clusters. Guest editors: Kristiaan Temst, Margriet J. Van Bael, Ewald Janssens, H.-G. Boyen and Françoise Remacle; International audience; The time-resolved photoelectron spectra, probing the non-adiabatic dynamics of CaAr n clusters excited by a pump pulse in the vicinity of the 4s4p 1P line of calcium, are simulated. The simulations involve Diatomics-In-Molecules modelling of the excited electronic structure, excited states dynamics with electronic transitions, and classical approximations to derive the time-resolved photoelectron spectra. The oscillations in the time-dependence of the spectra, associated with the relative motion of calcium with respect to the argon cluster, and the corresponding nonadiabatic relaxation processes are analysed according to cluster size (n ≈ 55 and 147), structure (icosahedral versus cuboctahedral shape) and local environment (substitution versus surface deposition of calcium, surface type).

Published
2013

15. A CASPT2 calculation of the lowest excited states of H2Fe(CO)4

Author

Chantal Daniel and Marie-Catherine Heitz

Subjects
Chemistry, Excited state, General Physics and Astronomy, Molecule, Physical and Theoretical Chemistry, Atomic physics, Wave function, Potential energy, Excitation, Spectral line
Abstract

CASPT2 calculations based on CASSCF reference wavefunctions, using large atomic natural orbital basis sets, are reported for the lowest excited states of H 2 Fe(CO) 4 . The excitation energies obtained with this accurate method are compared to the values from multireference contracted CI calculations based on a unique CASSCF wavefunction. This computational strategy is usually employed for the calculation of the one-electron properties, spin-orbit interaction or costly potential energy surfaces describing the photochemistry of organometallic molecules. The relative order of the excited states is not affected by this more refined treatment and the largest excitation energy differences are of the order of 0.25 eV for the lowest excited states. However, the computational strategy seems to have a dramatic influence on the results obtained for the highest excited states pointing out the limit of less accurate methods. The theoretical spectra obtained for this family of molecules must be compared with poorly resolved experimental spectra.

Published
1995

16. Spin–orbit induced radiationless transitions in organometallics: Quantum simulation of the 1E→3A1 intersystem crossing process in HCo(CO)4

Author

Marie-Catherine Heitz, Jörn Manz, Carl Ribbing, and Chantal Daniel

Subjects
Intersystem crossing, Chemical bond, Hydrogen bond, Chemistry, Excited state, Photodissociation, General Physics and Astronomy, Singlet state, Physical and Theoretical Chemistry, Atomic physics, Dissociation (chemistry), Reaction coordinate
Abstract

A theoretical description of the ‘‘fast’’ (

Published
1995

17. Relaxation dynamics of photoexcited calcium deposited on argon clusters: theoretical simulation of time-resolved photoelectron spectra

Author

Laurent Teixidor, Fernand Spiegelman, Nguyen-Thi Van-Oanh, Marie-Catherine Heitz, Modélisation, Agrégats, Dynamique (LCPQ) (MAD), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Laboratoire de Photophysique Moléculaire (PPM), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3)

Subjects
Argon, 010304 chemical physics, Chemistry, chemistry.chemical_element, Chromophore, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, Photoexcitation, 13. Climate action, Ab initio quantum chemistry methods, Atomic electron transition, Excited state, 0103 physical sciences, Vibrational energy relaxation, Physics::Atomic and Molecular Clusters, Relaxation (physics), Physical and Theoretical Chemistry, Atomic physics, Physics::Chemical Physics, [CHIM.OTHE]Chemical Sciences/Other
Abstract

International audience; Relaxation dynamics following photoexcitation of a calcium atom deposited on an icosahedral-like argon cluster Ar(n) (n approximately = 55) is investigated through theoretical simulations. Based on ab initio calculations of the CaAr molecule, a diatomics-in-molecules model is set up to efficiently describe the electronic excited states of the system. The excited state dynamics is studied using molecular dynamics with electronic transitions (Tully, J. C. J. Chem. Phys. 1990, 93, 1061). The signature of this dynamics in the time-resolved photoelectron spectra is investigated, to assess the possibility of detecting competing vibrational and electronic relaxations through pump-probe experiments. The vibrational relaxation, influenced by nonadiabatic transitions, can clearly be seen in the time-resolved photoelectron spectra. The details of the electronic relaxation, as well as the possible ejection of the chromophore, are found to be sensitive to the local environment of the calcium atom deposited on the argon cluster.

Published
2010

18. Evidence for a non-Rydberg molecular doubly excited state of Ca2

Author

Marc-André Gaveau, Thomas Bouissou, G. Durand, Marie-Catherine Heitz, J. M. Mestdagh, Fernand Spiegelman, Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Modélisation, Agrégats, Dynamique (LCPQ) (MAD), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)

Subjects
010304 chemical physics, Chemistry, Avoided crossing, Ab initio, General Physics and Astronomy, 01 natural sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Dipole, symbols.namesake, Excited state, 0103 physical sciences, Rydberg formula, symbols, Molecular orbital, Physical and Theoretical Chemistry, Atomic physics, 010306 general physics, Adiabatic process, Excitation
Abstract

We report experimental and theoretical evidence of a non-Rydberg molecular doubly excited state of Ca 2 involving excited molecular orbitals mixing 4p and 3d characters. The excitation spectrum of Ca 2 , carried by helium or argon clusters, is recorded experimentally in the range 25 600–27 800 cm −1 , displaying a bimodal structure. The latter is interpreted from ab initio calculation and analysis of the adiabatic states of Ca 2 up to doubly excited asymptotes Ca(4p3d 1 D) + Ca(4s 2 1 S) and Ca(4s3d 3 D) + Ca(4s4p 3 P), and the relevant dipole transition moments. The bimodal structure is assigned as resulting from the avoided crossing between adiabatic states 3 1 Π u and 4 1 Π u , reflecting the mixing of doubly excited configurations and absorbing singly excited configurations.

Published
2009

19. Ultrafast excited state dynamics of the Na3F cluster: quantum wave packet and classical trajectory calculations compared to experimental results

Author

G. Durand, Roland Mitrić, Marie-Catherine Heitz, Vlasta Bonačić-Koutecký, Christoph Meier, Fernand Spiegelman, Laboratoire de Physique Quantique (LPQ), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Théorie (LCAR), Laboratoire Collisions Agrégats Réactivité (LCAR), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut fur Chemie, Humboldt-Universität zu Berlin, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées

Subjects
010304 chemical physics, Chemistry, Wave packet, quantum wave packet, [PHYS.PHYS.PHYS-ATM-PH]Physics [physics]/Physics [physics]/Atomic and Molecular Clusters [physics.atm-clus], General Physics and Astronomy, alkali-halide, dynamics, 01 natural sciences, Photoexcitation, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Ab initio quantum chemistry methods, Quantum mechanics, Ionization, Excited state, 0103 physical sciences, Cluster (physics), classical trajectory, Physical and Theoretical Chemistry, Atomic physics, 010306 general physics, Mechanical wave, cluster, theory, Quantum
Abstract

Short-time, excited-state dynamics of the lowest isomer of the Na(3)F cluster is studied theoretically in order to interpret the features of recent time-resolved pump-probe ionization experiments [J. M. L'Hermite, V. Blanchet, A. Le Padellec, B. Lamory, and P. Labastie, Eur. Phys. J. D 28, 361 (2004)]. In the present paper, we propose an identification of the vibrational motion responsible for the oscillations in the ion signal, on the basis of quantum mechanical wave packet propagations and classical trajectory calculations. The good agreement between experiment and theory allows for a clear interpretation of the detected dynamics.

Published
2004

20. Different approaches for the calculation of electronic excited states of nonstoichiometric alkali halide clusters: The example of Na3F

Author

Vlasta Bonačić-Koutecký, Roland Mitrić, Marie-Catherine Heitz, Fernand Spiegelman, Christoph Meier, J. Pittner, G. Durand, Laboratoire de Physique Quantique (LPQ), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Théorie (LCAR), Laboratoire Collisions Agrégats Réactivité (LCAR), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Institut für Chemie [HU Berlin], Humboldt-Universität zu Berlin, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences [Prague] (CAS), Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)

Subjects
ab-initio, 010304 chemical physics, Absorption spectroscopy, potential energy surfaces, Chemistry, General Physics and Astronomy, Multireference configuration interaction, alkali-halide, Electronic structure, 7. Clean energy, 01 natural sciences, Potential energy, Pseudopotential, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Excited state, 0103 physical sciences, Cluster (physics), Density functional theory, Physical and Theoretical Chemistry, Atomic physics, 010306 general physics, cluster, theory
Abstract

The electronic structure and excited states of the Na(3)F cluster are investigated using different approximate, but numerically efficient, computational schemes, such as a 2e hybrid quantum/classical pseudopotential model with full-configuration interaction or time-dependent density-functional theory. Various quantities such as geometries and transition energies are compared with results previously obtained by multireference configuration interaction calculations, taken as reference data. The potential energy surfaces of the lowest excited states are investigated and the finite-temperature absorption spectra are calculated. The good agreement with recent beam experiments [J.-M. L'Hermite, V. Blanchet, A. Le Padellec, B. Lamory, and P. Labastie, Eur. Phys. J. D 28, 361 (2004)] leads to the conclusion that the absorption spectrum observed experimentally corresponds to the lowest energy isomer which has a C(2v) planar rhombic geometry.

Published
2004

21. Études théoriques de la dynamique des états excités de petits agrégats de fluorure de sodium

Author

Christoph Meier, Marie-Catherine Heitz, G. Durand, and Fernand Spiegelman

Subjects
Physics, General Physics and Astronomy, Physical chemistry
Abstract

La dynamique des etats excites des agregats Na 2 F et Na 3 F a ete etudiee par des methodes quantiques de propagation de paquets d'ondes. Les resultats de nos calculs permettent par confrontation avec des donnees experimentales recentes d'elucider la dynamique vibrationnelle dans des etats excites.

Published
2004

22. Laser control of vibrational excitation in carboxyhemoglobin: A quantum wave packet study

Author

Marie-Catherine Heitz and Christoph Meier

Subjects
Carbon Monoxide, Binding Sites, Porphyrins, Chemistry, Iron, Lasers, Wave packet, Quantum dynamics, Far-infrared laser, Imidazoles, General Physics and Astronomy, Laser, Vibration, law.invention, Electromagnetic Fields, Carboxyhemoglobin, Models, Chemical, law, Coherent control, Potential energy surface, Physical and Theoretical Chemistry, Atomic physics, Quantum, Algorithms, Excitation
Abstract

A coherent control algorithm is applied to obtain complex-shaped infrared laser pulses for the selective vibrational excitation of carbon monoxide at the active site of carbonmonoxyhemoglobin, modeled by the six-coordinated iron-porphyrin-imidazole-CO complex. The influence of the distal histidine is taken into account by an additional imidazole molecule. Density-functional theory is employed to calculate a multidimensional ground-state potential energy surface, and the vibrational dynamics as well as the laser interaction is described by quantum wave-packet calculations. At each instant in time, the optimal electric field is calculated and used for the subsequent quantum dynamics. The results presented show that the control scheme is applicable to complex systems and that it yields laser pulses with complex time-frequency structures, which, nevertheless, have a clear physical interpretation.

Published
2005

23. Coupled Electronic and Structural Relaxation Pathways in the Postexcitation Dynamics of Rydberg States of BaArN Clusters

Author

Lionel Poisson, Marie-Catherine Heitz, Fernand Spiegelman, A. Masson, Marc-André Gaveau, Jean-Michel Mestdagh, Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Modélisation, Agrégats, Dynamique (LCPQ) (MAD), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)

Subjects
Physics, Photoemission spectroscopy, Barium Compounds, General Physics and Astronomy, PACS numbers: 31.70.Hq, 31.50.Gh, 33.60.+q, 36.40.-c, Models, Theoretical, Photochemical Processes, Molecular physics, Electronic states, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, symbols.namesake, symbols, Cluster (physics), Rydberg formula, Quantum Theory, Thermodynamics, Physics::Atomic Physics, Atomic physics, Argon, Hamiltonian (quantum mechanics)
Abstract

International audience; We investigate, theoretically, the joint relaxation of orbital and structure in postexcitation dynamics of Rydberg states of cluster BaArN (N=250). Mixed quantum-classical dynamics is used to account for the nonadiabatic transitions among more than 160 electronic states, represented via a diatomics-in-molecules Hamiltonian. The simulation illustrates the complex multistep relaxation processes and provides detailed insight in the mechanisms contributing to the final-time experimental photoelectron spectrum.

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