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A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz.

ABSTRACT: We develop and validate the XYGJ-OS functional, based on the adiabatic connection formalism and Görling-Levy perturbation theory to second order and using the opposite-spin (OS) ansatz combined with locality of electron correlation. XYGJ-OS with local implementation scales as N(3) with an overall accuracy of 1.28 kcal/mol for thermochemistry, bond dissociation energies, reaction barrier heights, and nonbonded interactions, comparable to that of 1.06 kcal/mol for the accurate coupled-cluster based G3 method (scales as N(7)) and much better than many popular density functional theory methods: B3LYP (4.98), PBE0 (4.36), and PBE (12.10).

SUBMITTER: Zhang IY

PROVIDER: S-EPMC3250148 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz.

Zhang Igor Ying IY Xu Xin X Jung Yousung Y Goddard William A WA

Proceedings of the National Academy of Sciences of the United States of America 20111123 50

We develop and validate the XYGJ-OS functional, based on the adiabatic connection formalism and Görling-Levy perturbation theory to second order and using the opposite-spin (OS) ansatz combined with locality of electron correlation. XYGJ-OS with local implementation scales as N(3) with an overall accuracy of 1.28 kcal/mol for thermochemistry, bond dissociation energies, reaction barrier heights, and nonbonded interactions, comparable to that of 1.06 kcal/mol for the accurate coupled-cluster base ...[more]

PMID: 22114187

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A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz.

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A fast doubly hybrid density functional method close to chemical accuracy using a local opposite spin ansatz.

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