Approximate spin projected spinunrestricted density functional theory method: Application to diradical character dependences of second hyperpolarizabilities
Abstract
We develop a novel method for the calculation and the analysis of the oneelectron reduced densities in openshell molecular systems using the natural orbitals and approximate spin projected occupation numbers obtained from broken symmetry (BS), i.e., spinunrestricted (U), density functional theory (DFT) calculations. The performance of this approximate spin projection (ASP) scheme is examined for the diradical character dependence of the second hyperpolarizability (γ) using several exchangecorrelation functionals, i.e., hybrid and longrange corrected UDFT schemes. It is found that the ASPLCUBLYP method with a range separating parameter μ = 0.47 reproduces semiquantitatively the stronglycorrelated [UCCSD(T)] result for pquinodimethane, i.e., the γ variation as a function of the diradical character.
 Authors:
 Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 5608531 (Japan)
 Laboratoire de Chimie Théorique, Facultés Universitaires NotreDame de la Paix (FUNDP), rue de Bruxelles, 61, 5000 Namur (Belgium)
 Publication Date:
 OSTI Identifier:
 22390901
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1642; Journal Issue: 1; Conference: ICCMSE2010: International Conference of Computational Methods in Sciences and Engineering 2010, Kos (Greece), 38 Oct 2010; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; APPROXIMATIONS; DENSITY FUNCTIONAL METHOD; ELECTRONS; PERFORMANCE; POLARIZABILITY; SPIN; SYMMETRY BREAKING; VARIATIONS
Citation Formats
Nakano, Masayoshi, Email: mnaka@cheng.es.osakau.ac.jp, Minami, Takuya, Email: mnaka@cheng.es.osakau.ac.jp, Fukui, Hitoshi, Email: mnaka@cheng.es.osakau.ac.jp, Yoneda, Kyohei, Email: mnaka@cheng.es.osakau.ac.jp, Shigeta, Yasuteru, Email: mnaka@cheng.es.osakau.ac.jp, Kishi, Ryohei, Email: mnaka@cheng.es.osakau.ac.jp, Champagne, Benoît, and Botek, Edith. Approximate spin projected spinunrestricted density functional theory method: Application to diradical character dependences of second hyperpolarizabilities. United States: N. p., 2015.
Web. doi:10.1063/1.4906627.
Nakano, Masayoshi, Email: mnaka@cheng.es.osakau.ac.jp, Minami, Takuya, Email: mnaka@cheng.es.osakau.ac.jp, Fukui, Hitoshi, Email: mnaka@cheng.es.osakau.ac.jp, Yoneda, Kyohei, Email: mnaka@cheng.es.osakau.ac.jp, Shigeta, Yasuteru, Email: mnaka@cheng.es.osakau.ac.jp, Kishi, Ryohei, Email: mnaka@cheng.es.osakau.ac.jp, Champagne, Benoît, & Botek, Edith. Approximate spin projected spinunrestricted density functional theory method: Application to diradical character dependences of second hyperpolarizabilities. United States. doi:10.1063/1.4906627.
Nakano, Masayoshi, Email: mnaka@cheng.es.osakau.ac.jp, Minami, Takuya, Email: mnaka@cheng.es.osakau.ac.jp, Fukui, Hitoshi, Email: mnaka@cheng.es.osakau.ac.jp, Yoneda, Kyohei, Email: mnaka@cheng.es.osakau.ac.jp, Shigeta, Yasuteru, Email: mnaka@cheng.es.osakau.ac.jp, Kishi, Ryohei, Email: mnaka@cheng.es.osakau.ac.jp, Champagne, Benoît, and Botek, Edith. 2015.
"Approximate spin projected spinunrestricted density functional theory method: Application to diradical character dependences of second hyperpolarizabilities". United States.
doi:10.1063/1.4906627.
@article{osti_22390901,
title = {Approximate spin projected spinunrestricted density functional theory method: Application to diradical character dependences of second hyperpolarizabilities},
author = {Nakano, Masayoshi, Email: mnaka@cheng.es.osakau.ac.jp and Minami, Takuya, Email: mnaka@cheng.es.osakau.ac.jp and Fukui, Hitoshi, Email: mnaka@cheng.es.osakau.ac.jp and Yoneda, Kyohei, Email: mnaka@cheng.es.osakau.ac.jp and Shigeta, Yasuteru, Email: mnaka@cheng.es.osakau.ac.jp and Kishi, Ryohei, Email: mnaka@cheng.es.osakau.ac.jp and Champagne, Benoît and Botek, Edith},
abstractNote = {We develop a novel method for the calculation and the analysis of the oneelectron reduced densities in openshell molecular systems using the natural orbitals and approximate spin projected occupation numbers obtained from broken symmetry (BS), i.e., spinunrestricted (U), density functional theory (DFT) calculations. The performance of this approximate spin projection (ASP) scheme is examined for the diradical character dependence of the second hyperpolarizability (γ) using several exchangecorrelation functionals, i.e., hybrid and longrange corrected UDFT schemes. It is found that the ASPLCUBLYP method with a range separating parameter μ = 0.47 reproduces semiquantitatively the stronglycorrelated [UCCSD(T)] result for pquinodimethane, i.e., the γ variation as a function of the diradical character.},
doi = {10.1063/1.4906627},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1642,
place = {United States},
year = 2015,
month = 1
}

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