Development of highly accurate approximate scheme for computing the charge transfer integral
Abstract
The charge transfer integral is a key parameter required by various theoretical models to describe charge transport properties, e.g., in organic semiconductors. The accuracy of this important property depends on several factors, which include the level of electronic structure theory and internal simplifications of the applied formalism. The goal of this paper is to identify the performance of various approximate approaches of the latter category, while using the high level equationofmotion coupled cluster theory for the electronic structure. The calculations have been performed on the ethylene dimer as one of the simplest model systems. By studying different spatial perturbations, it was shown that while both energy split in dimer and fragment charge difference methods are equivalent with the exact formulation for symmetrical displacements, they are less efficient when describing transfer integral along the asymmetric alteration coordinate. Since the “exact” scheme was found computationally expensive, we examine the possibility to obtain the asymmetric fluctuation of the transfer integral by a Taylor expansion along the coordinate space. By exploring the efficiency of this novel approach, we show that the Taylor expansion scheme represents an attractive alternative to the “exact” calculations due to a substantial reduction of computational costs, when a considerably largemore »
 Authors:
 Laboratory for Theoretical Chemistry, Institute of Chemistry, Eötvös Loránd University, P.O. Box 32, H1518 Budapest (Hungary)
 Publication Date:
 OSTI Identifier:
 22493534
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 7; 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; ASYMMETRY; CHARGE TRANSPORT; DIMERS; ELECTRONIC STRUCTURE; EQUATIONS OF MOTION; ETHYLENE; EXPANSION; FLUCTUATIONS; INTEGRALS; MOLECULES; ORGANIC SEMICONDUCTORS; POTENTIAL ENERGY; REDUCTION; SURFACES; TEMPERATURE RANGE 02730400 K
Citation Formats
Pershin, Anton, and Szalay, Péter G. Development of highly accurate approximate scheme for computing the charge transfer integral. United States: N. p., 2015.
Web. doi:10.1063/1.4928053.
Pershin, Anton, & Szalay, Péter G. Development of highly accurate approximate scheme for computing the charge transfer integral. United States. doi:10.1063/1.4928053.
Pershin, Anton, and Szalay, Péter G. 2015.
"Development of highly accurate approximate scheme for computing the charge transfer integral". United States.
doi:10.1063/1.4928053.
@article{osti_22493534,
title = {Development of highly accurate approximate scheme for computing the charge transfer integral},
author = {Pershin, Anton and Szalay, Péter G.},
abstractNote = {The charge transfer integral is a key parameter required by various theoretical models to describe charge transport properties, e.g., in organic semiconductors. The accuracy of this important property depends on several factors, which include the level of electronic structure theory and internal simplifications of the applied formalism. The goal of this paper is to identify the performance of various approximate approaches of the latter category, while using the high level equationofmotion coupled cluster theory for the electronic structure. The calculations have been performed on the ethylene dimer as one of the simplest model systems. By studying different spatial perturbations, it was shown that while both energy split in dimer and fragment charge difference methods are equivalent with the exact formulation for symmetrical displacements, they are less efficient when describing transfer integral along the asymmetric alteration coordinate. Since the “exact” scheme was found computationally expensive, we examine the possibility to obtain the asymmetric fluctuation of the transfer integral by a Taylor expansion along the coordinate space. By exploring the efficiency of this novel approach, we show that the Taylor expansion scheme represents an attractive alternative to the “exact” calculations due to a substantial reduction of computational costs, when a considerably large region of the potential energy surface is of interest. Moreover, we show that the Taylor expansion scheme, irrespective of the dimer symmetry, is very accurate for the entire range of geometry fluctuations that cover the space the molecule accesses at room temperature.},
doi = {10.1063/1.4928053},
journal = {Journal of Chemical Physics},
number = 7,
volume = 143,
place = {United States},
year = 2015,
month = 8
}

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