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Generalizing Double-Hybrid Density Functionals: Impact of Higher-Order Perturbation Terms.

ABSTRACT: Connections between the Görling-Levy (GL) perturbation theory and the parameters of double-hybrid (DH) density functional are established via adiabatic connection formalism. Moreover, we present a more general DH density functional theory, where the higher-order perturbation terms beyond the second-order GL2 one, such as GL3 and GL4, also contribute. It is shown that a class of DH functionals including previously proposed ones can be formed using the present construction. Based on the proposed formalism, we assess the performance of higher-order DH and long-range corrected DH formed on the Perdew-Burke-Ernzerhof (PBE) semilocal functional and second-order GL2 correlation energy. The underlying construction of DH functionals based on the generalized many-body perturbation approaches is physically appealing in terms of the development of the non-local forms using more accurate and sophisticated semilocal functionals.

SUBMITTER: Jana S

PROVIDER: S-EPMC7735712 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Generalizing Double-Hybrid Density Functionals: Impact of Higher-Order Perturbation Terms.

Jana Subrata S Śmiga Szymon S Constantin Lucian A LA Samal Prasanjit P

Journal of chemical theory and computation 20201118 12

Connections between the Görling-Levy (GL) perturbation theory and the parameters of double-hybrid (DH) density functional are established via adiabatic connection formalism. Moreover, we present a more general DH density functional theory, where the higher-order perturbation terms beyond the second-order GL2 one, such as GL3 and GL4, also contribute. It is shown that a class of DH functionals including previously proposed ones can be formed using the present construction. Based on the proposed f ...[more]

PMID: 33205659

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