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Title: Insights into the spurious long-range nature of local rs-dependent non-local exchange-correlation kernels

Abstract

A systematic route to go beyond the exact exchange plus random phase approximation (RPA) is to include a physical exchange-correlation kernel in the adiabatic-connection fluctuation-dissipation theorem. Previously, [D. Lu, J. Chem. Phys. 140, 18A520 (2014)], we found that non-local kernels with a screening length depending on the local Wigner-Seitz radius, r s(r), suffer an error associated with a spurious long-range repulsion in van der Waals bounded systems, which deteriorates the binding energy curve as compared to RPA. Here, we analyze the source of the error and propose to replace r s(r) by a global, average r s in the kernel. Exemplary studies with the Corradini, del Sole, Onida, and Palummo kernel show that while this change does not affect the already outstanding performance in crystalline solids, using an average r s significantly reduces the spurious long-range tail in the exchange-correlation kernel in van der Waals bounded systems. Finally, when this method is combined with further corrections using local dielectric response theory, the binding energy of the Kr dimer is improved three times as compared to RPA.

Authors:
ORCiD logo [1]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1303020
Alternate Identifier(s):
OSTI ID: 1283417
Report Number(s):
BNL-112515-2016-JA
Journal ID: ISSN 0021-9606; JCPSA6; R&D Project: 16068; KC0403020
Grant/Contract Number:
SC00112704; AC02-05CH11231; SC0012704
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 145; Journal Issue: 5; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Lu, Deyu. Insights into the spurious long-range nature of local rs-dependent non-local exchange-correlation kernels. United States: N. p., 2016. Web. doi:10.1063/1.4960381.
Lu, Deyu. Insights into the spurious long-range nature of local rs-dependent non-local exchange-correlation kernels. United States. doi:10.1063/1.4960381.
Lu, Deyu. Fri . "Insights into the spurious long-range nature of local rs-dependent non-local exchange-correlation kernels". United States. doi:10.1063/1.4960381. https://www.osti.gov/servlets/purl/1303020.
@article{osti_1303020,
title = {Insights into the spurious long-range nature of local rs-dependent non-local exchange-correlation kernels},
author = {Lu, Deyu},
abstractNote = {A systematic route to go beyond the exact exchange plus random phase approximation (RPA) is to include a physical exchange-correlation kernel in the adiabatic-connection fluctuation-dissipation theorem. Previously, [D. Lu, J. Chem. Phys. 140, 18A520 (2014)], we found that non-local kernels with a screening length depending on the local Wigner-Seitz radius, rs(r), suffer an error associated with a spurious long-range repulsion in van der Waals bounded systems, which deteriorates the binding energy curve as compared to RPA. Here, we analyze the source of the error and propose to replace rs(r) by a global, average rs in the kernel. Exemplary studies with the Corradini, del Sole, Onida, and Palummo kernel show that while this change does not affect the already outstanding performance in crystalline solids, using an average rs significantly reduces the spurious long-range tail in the exchange-correlation kernel in van der Waals bounded systems. Finally, when this method is combined with further corrections using local dielectric response theory, the binding energy of the Kr dimer is improved three times as compared to RPA.},
doi = {10.1063/1.4960381},
journal = {Journal of Chemical Physics},
number = 5,
volume = 145,
place = {United States},
year = {Fri Aug 05 00:00:00 EDT 2016},
month = {Fri Aug 05 00:00:00 EDT 2016}
}

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