Implementation of the CCSD(T)-F12 method using cusp conditions

被引：71

作者：

Bokhan, Denis ^{[1
,2
]}

Ten-No, Seiichiro ^{[1
,2
]}

Noga, Jozef ^{[3
,4
]}

机构：

[1] Nagoya Univ, Grad Sch Informat Sci, Chikusa Ku, Nagoya, Aichi 4648601, Japan

[2] Japan Sci & Technol Agcy, CREST, Kawaguchi, Saitama 3320012, Japan

[3] Comenius Univ, Fac Nat Sci, Dept Phys & Theoret Chem, SK-84215 Bratislava, Slovakia

[4] Slovak Acad Sci, Inst Inorgan Chem, SK-84536 Bratislava, Slovakia

来源：

PHYSICAL CHEMISTRY CHEMICAL PHYSICS | 2008年 / 10卷 / 23期

关键词：

D O I：

10.1039/b803426p

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The explicitly-correlated coupled-cluster singles and doubles with perturbative triples method (CCSD(T)-F12) is implemented using the cusp conditions. Numerical tests for a set of 16 molecules have shown agreement of correlation energies within 1 mE(h) between the cusp-condition and fully-optimized CCSD(T)-F12 methods. Benchmark calculations on 13 chemical reactions with the cusp-condition CCSD(T)-F12 method reproduce experimental enthalpies within 2 kJ mol(-1). It is also shown that regular unitary-invariant ansatz cannot exactly satisfy singlet and triplet cusp conditions in open-shell situations. We present an extended ansatz which can handle both conditions exactly.

引用

页码：3320 / 3326

页数：7

共 51 条

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