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Title: Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme

Abstract

Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in themore » subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations.« less

Authors:
 [1]; ;  [2]
  1. Peter Grunberg Institut (PGI) Forschungszentrum Jülich, D-52425 Jülich (Germany)
  2. Institute for Advanced Materials, Physicochemical Processes, Nanotechnology and Microsystems, ‘Demokritos’ National Center for Scientific Research, 15310 Athens (Greece)
Publication Date:
OSTI Identifier:
22254155
Resource Type:
Journal Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 140; Journal Issue: 16; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; EXCITATION; EXCITED STATES; GROUND STATES; HARTREE-FOCK METHOD; HYDROCARBONS; MINIMIZATION; PARTICLES; PHOTOVOLTAIC EFFECT

Citation Formats

Theophilou, Iris, Tassi, M., and Thanos, S. Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme. United States: N. p., 2014. Web. doi:10.1063/1.4871502.
Theophilou, Iris, Tassi, M., & Thanos, S. Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme. United States. https://doi.org/10.1063/1.4871502
Theophilou, Iris, Tassi, M., and Thanos, S. 2014. "Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme". United States. https://doi.org/10.1063/1.4871502.
@article{osti_22254155,
title = {Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme},
author = {Theophilou, Iris and Tassi, M. and Thanos, S.},
abstractNote = {Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in the subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations.},
doi = {10.1063/1.4871502},
url = {https://www.osti.gov/biblio/22254155}, journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 16,
volume = 140,
place = {United States},
year = {Mon Apr 28 00:00:00 EDT 2014},
month = {Mon Apr 28 00:00:00 EDT 2014}
}