Transition matrices and orbitals from reduced density matrix theory
Abstract
In this contribution, we report two different methodologies for characterizing the electronic structure reorganization occurring when a chromophore undergoes an electronic transition. For the first method, we start by setting the theoretical background necessary to the reinterpretation through simple tensor analysis of (i) the transition density matrix and (ii) the natural transition orbitals in the scope of reduced density matrix theory. This novel interpretation is made more clear thanks to a short compendium of the oneparticle reduced density matrix theory in a Fock space. The formalism is further applied to two different classes of excited states calculation methods, both requiring a singledeterminant reference, that express an excited state as a holeparticle monoexcited configurations expansion, to which particlehole correlation is coupled (timedependent HartreeFock/timedependent density functional theory) or not (configuration interaction single/TammDancoff approximation). For the second methodology presented in this paper, we introduce a novel and complementary concept related to electronic transitions with the canonical transition density matrix and the canonical transition orbitals. Their expression actually reflects the electronic cloud polarisation in the orbital space with a decomposition based on the actual contribution of oneparticle excitations from occupied canonical orbitals to virtual ones. This approach validates our novel interpretation of the transitionmore »
 Authors:
 Université de Lorraine – Nancy, ThéorieModélisationSimulation, SRSMC, Boulevard des Aiguillettes 54506, VandoeuvrelèsNancy (France)
 (France)
 (Belgium)
 Publication Date:
 OSTI Identifier:
 22490823
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 24; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 97 MATHEMATICAL METHODS AND COMPUTING; CONFIGURATION INTERACTION; DECOMPOSITION; DENSITY FUNCTIONAL METHOD; DENSITY MATRIX; ELECTRONIC STRUCTURE; EXCITATION; EXCITED STATES; HARTREEFOCK METHOD; POLARIZATION; TIME DEPENDENCE; VECTORS
Citation Formats
Etienne, Thibaud, CNRS, ThéorieModélisationSimulation, SRSMC, Boulevard des Aiguillettes 54506, VandoeuvrelèsNancy, and Unité de Chimie Physique Théorique et Structurale, Université de Namur, Rue de Bruxelles 61, 5000 Namur. Transition matrices and orbitals from reduced density matrix theory. United States: N. p., 2015.
Web. doi:10.1063/1.4922780.
Etienne, Thibaud, CNRS, ThéorieModélisationSimulation, SRSMC, Boulevard des Aiguillettes 54506, VandoeuvrelèsNancy, & Unité de Chimie Physique Théorique et Structurale, Université de Namur, Rue de Bruxelles 61, 5000 Namur. Transition matrices and orbitals from reduced density matrix theory. United States. doi:10.1063/1.4922780.
Etienne, Thibaud, CNRS, ThéorieModélisationSimulation, SRSMC, Boulevard des Aiguillettes 54506, VandoeuvrelèsNancy, and Unité de Chimie Physique Théorique et Structurale, Université de Namur, Rue de Bruxelles 61, 5000 Namur. Sun .
"Transition matrices and orbitals from reduced density matrix theory". United States.
doi:10.1063/1.4922780.
@article{osti_22490823,
title = {Transition matrices and orbitals from reduced density matrix theory},
author = {Etienne, Thibaud and CNRS, ThéorieModélisationSimulation, SRSMC, Boulevard des Aiguillettes 54506, VandoeuvrelèsNancy and Unité de Chimie Physique Théorique et Structurale, Université de Namur, Rue de Bruxelles 61, 5000 Namur},
abstractNote = {In this contribution, we report two different methodologies for characterizing the electronic structure reorganization occurring when a chromophore undergoes an electronic transition. For the first method, we start by setting the theoretical background necessary to the reinterpretation through simple tensor analysis of (i) the transition density matrix and (ii) the natural transition orbitals in the scope of reduced density matrix theory. This novel interpretation is made more clear thanks to a short compendium of the oneparticle reduced density matrix theory in a Fock space. The formalism is further applied to two different classes of excited states calculation methods, both requiring a singledeterminant reference, that express an excited state as a holeparticle monoexcited configurations expansion, to which particlehole correlation is coupled (timedependent HartreeFock/timedependent density functional theory) or not (configuration interaction single/TammDancoff approximation). For the second methodology presented in this paper, we introduce a novel and complementary concept related to electronic transitions with the canonical transition density matrix and the canonical transition orbitals. Their expression actually reflects the electronic cloud polarisation in the orbital space with a decomposition based on the actual contribution of oneparticle excitations from occupied canonical orbitals to virtual ones. This approach validates our novel interpretation of the transition density matrix elements in terms of the Euclidean norm of elementary transition vectors in a linear tensor space. A proper use of these new concepts leads to the conclusion that despite the different principles underlying their construction, they provide two equivalent excited states topological analyses. This connexion is evidenced through simple illustrations of (in)organic dyes electronic transitions analysis.},
doi = {10.1063/1.4922780},
journal = {Journal of Chemical Physics},
number = 24,
volume = 142,
place = {United States},
year = {Sun Jun 28 00:00:00 EDT 2015},
month = {Sun Jun 28 00:00:00 EDT 2015}
}

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