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Title: Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting

Abstract

A transition charge, dipole, and quadrupole from electrostatic potential (TrESP-CDQ) method for electronic coupling calculations is proposed. The TrESP method is based on the classical description of electronic Coulomb interaction between transition densities for individual molecules. In the original TrESP method, only the transition charge interactions were considered as the electronic coupling. In the present study, the TrESP method is extended to include the contributions from the transition dipoles and quadrupoles as well as the transition charges. Hence, the self-consistent transition density is employed in the ESP fitting procedure. To check the accuracy of the present approach, several test calculations are performed to a helium dimer, a methane dimer, and an ethylene dimer. As a result, the TrESP-CDQ method gives a much improved description of the electronic coupling, compared with the original TrESP method. The calculated results also show that the self-consistent treatment to the transition densities contributes significantly to the accuracy of the electronic coupling calculations. Based on the successful description of the electronic coupling, the contributions to the electronic coupling are also analyzed. This analysis clearly shows a negligible contribution of the transition charge interaction to the electronic coupling. Hence, the distribution of the transition density is foundmore » to strongly influence the magnitudes of the transition charges, dipoles, and quadrupoles. The present approach is useful for analyzing and understanding the mechanism of excitation-energy transfer.« less

Authors:
 [1]
  1. Department of Computational Science, Graduate School of System Informatics, Kobe University, 1-1, Rokkodai, Nada, Kobe 657-8501 (Japan)
Publication Date:
OSTI Identifier:
22413261
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 21; Other Information: (c) 2014 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; ACCURACY; COUPLING; DENSITY; DIMERS; DIPOLES; DISTRIBUTION; ENERGY TRANSFER; ETHYLENE; EXCITATION; HELIUM; INTERACTIONS; METHANE; MOLECULES; QUADRUPOLES

Citation Formats

Fujimoto, Kazuhiro J., E-mail: fujimoto@ruby.kobe-u.ac.jp. Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting. United States: N. p., 2014. Web. doi:10.1063/1.4902758.
Fujimoto, Kazuhiro J., E-mail: fujimoto@ruby.kobe-u.ac.jp. Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting. United States. doi:10.1063/1.4902758.
Fujimoto, Kazuhiro J., E-mail: fujimoto@ruby.kobe-u.ac.jp. Sun . "Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting". United States. doi:10.1063/1.4902758.
@article{osti_22413261,
title = {Electronic coupling calculations with transition charges, dipoles, and quadrupoles derived from electrostatic potential fitting},
author = {Fujimoto, Kazuhiro J., E-mail: fujimoto@ruby.kobe-u.ac.jp},
abstractNote = {A transition charge, dipole, and quadrupole from electrostatic potential (TrESP-CDQ) method for electronic coupling calculations is proposed. The TrESP method is based on the classical description of electronic Coulomb interaction between transition densities for individual molecules. In the original TrESP method, only the transition charge interactions were considered as the electronic coupling. In the present study, the TrESP method is extended to include the contributions from the transition dipoles and quadrupoles as well as the transition charges. Hence, the self-consistent transition density is employed in the ESP fitting procedure. To check the accuracy of the present approach, several test calculations are performed to a helium dimer, a methane dimer, and an ethylene dimer. As a result, the TrESP-CDQ method gives a much improved description of the electronic coupling, compared with the original TrESP method. The calculated results also show that the self-consistent treatment to the transition densities contributes significantly to the accuracy of the electronic coupling calculations. Based on the successful description of the electronic coupling, the contributions to the electronic coupling are also analyzed. This analysis clearly shows a negligible contribution of the transition charge interaction to the electronic coupling. Hence, the distribution of the transition density is found to strongly influence the magnitudes of the transition charges, dipoles, and quadrupoles. The present approach is useful for analyzing and understanding the mechanism of excitation-energy transfer.},
doi = {10.1063/1.4902758},
journal = {Journal of Chemical Physics},
number = 21,
volume = 141,
place = {United States},
year = {Sun Dec 07 00:00:00 EST 2014},
month = {Sun Dec 07 00:00:00 EST 2014}
}
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