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Basis-set completeness profiles in two dimensions

✍ Scribed by Alexander A. Auer; Trygve Helgaker; Wim Klopper

Publisher
John Wiley and Sons
Year
2002
Tongue
English
Weight
322 KB
Volume
23
Category
Article
ISSN
0192-8651

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✦ Synopsis

Abstract

A two‐electron basis‐set completeness profile is proposed by analogy with the one‐electron profile introduced by D. P. Chong (Can J Chem 1995, 73, 79). It is defined as Y(α,β)=∑~m~∑~n~〈G~α~(1)G~β~(2)∣(1/r~12~)∣Ψ~m~(1)Ψ~n~(2)〉〈Ψ~m~(1)Ψ~n~(2)∣r~12~∣G~α~(1)G~β~(2)〉 and motivated by the expression for the basis‐set truncation correction that occurs in the framework of explicitly correlated methods (G~α~ is a scanning Gaussian‐type orbital of exponent α and {Ψ~m~} is the orthonormalized one‐electron basis under study). The two‐electron basis‐set profiles provide a visual assessment of the suitability of basis sets to describe electron‐correlation effects. Furthermore, they provide the opportunity to assess the quality of the basis set as a whole—not only of the individual angular momentum subspaces, as is the case for the one‐electron basis‐set profiles. The two‐electron completeness profiles of the cc‐pV__X__Z (X=D, T, Q), aug‐cc‐pVTZ, cc‐pCVTZ, and SVP‐auxiliary basis sets for the carbon atom are presented as illustrative examples. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 420–425, 2002

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