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Title: Exact-exchange time-dependent density-functional theory with the frequency-dependent kernel

Abstract

The effects of the adiabatic approximation in time-dependent density-functional theory (TDDFT) on dynamic polarizabilities and van der Waals C{sub 6} coefficients have been analyzed quantitatively. These effects are shown to be small in the off-resonance region of the perturbation frequencies by comparing the results from the exact-exchange TDDFT employing the optimized effective potentials and the corresponding frequency-dependent kernel [time-dependent optimized effective potentials (TDOEP)] and those from the frequency-independent kernel [adiabatic TDOEP (ATDOEP)]. The magnitude of the computed dynamic polarizabilities near the static limit is found to be in the order: time-dependent Hartree-Fock (TDHF)>ATDOEP>TDOEP, whereas that of C{sub 6} is: TDHF>TDOEP>ATDOEP.

Authors:
; ;  [1];  [2]
  1. Department of Applied Chemistry, School of Engineering, University of Tokyo, Hongo 7-3-1, Tokyo 113-8656 (Japan)
  2. (United States)
Publication Date:
OSTI Identifier:
20786623
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.73.010502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ADIABATIC APPROXIMATION; DENSITY FUNCTIONAL METHOD; DISTURBANCES; FREQUENCY DEPENDENCE; HARTREE-FOCK METHOD; KERNELS; PERTURBATION THEORY; POLARIZABILITY; POTENTIALS; RESONANCE; TIME DEPENDENCE; VAN DER WAALS FORCES

Citation Formats

Shigeta, Yasuteru, Hirao, Kimihiko, Hirata, So, and Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611-8435. Exact-exchange time-dependent density-functional theory with the frequency-dependent kernel. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Shigeta, Yasuteru, Hirao, Kimihiko, Hirata, So, & Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611-8435. Exact-exchange time-dependent density-functional theory with the frequency-dependent kernel. United States. doi:10.1103/PHYSREVA.73.0.
Shigeta, Yasuteru, Hirao, Kimihiko, Hirata, So, and Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611-8435. Sun . "Exact-exchange time-dependent density-functional theory with the frequency-dependent kernel". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20786623,
title = {Exact-exchange time-dependent density-functional theory with the frequency-dependent kernel},
author = {Shigeta, Yasuteru and Hirao, Kimihiko and Hirata, So and Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611-8435},
abstractNote = {The effects of the adiabatic approximation in time-dependent density-functional theory (TDDFT) on dynamic polarizabilities and van der Waals C{sub 6} coefficients have been analyzed quantitatively. These effects are shown to be small in the off-resonance region of the perturbation frequencies by comparing the results from the exact-exchange TDDFT employing the optimized effective potentials and the corresponding frequency-dependent kernel [time-dependent optimized effective potentials (TDOEP)] and those from the frequency-independent kernel [adiabatic TDOEP (ATDOEP)]. The magnitude of the computed dynamic polarizabilities near the static limit is found to be in the order: time-dependent Hartree-Fock (TDHF)>ATDOEP>TDOEP, whereas that of C{sub 6} is: TDHF>TDOEP>ATDOEP.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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  • We present a range-separated linear-response time-dependent density-functional theory (TDDFT) which combines a density-functional approximation for the short-range response kernel and a frequency-dependent second-order Bethe-Salpeter approximation for the long-range response kernel. This approach goes beyond the adiabatic approximation usually used in linear-response TDDFT and aims at improving the accuracy of calculations of electronic excitation energies of molecular systems. A detailed derivation of the frequency-dependent second-order Bethe-Salpeter correlation kernel is given using many-body Green-function theory. Preliminary tests of this range-separated TDDFT method are presented for the calculation of excitation energies of the He and Be atoms and small molecules (H{sub 2}, N{submore » 2}, CO{sub 2}, H{sub 2}CO, and C{sub 2}H{sub 4}). The results suggest that the addition of the long-range second-order Bethe-Salpeter correlation kernel overall slightly improves the excitation energies.« less
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