Approximate fourth‐order perturbation theory of the electron correlation energy

International Journal of Quantum Chemistry - Tập 14 Số 1 - Trang 91-100 - 1978
R. Krishnan1, John A. Pople1
1Department of Chemistry, Carnegie-Mellon University Pittsburgh, Pennsylvania 15213, U.S.A.

Tóm tắt

Abstract

An approximate fourth‐order expression for the electron correlation energy in the Møller–Plesset perturbation scheme is proposed. It takes into account all the contributions to the fourthorder energy neglecting only those of the triple‐substituted determinants. It is size consistent and correct to fourth order for an assembly of isolated two‐electron systems. Illustrative calculations are reported for a series of small molecules.

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Tài liệu tham khảo

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