论文信息 - A new method for large-scale Cl calculations

A new method for large-scale Cl calculations

Abstract A new method for obtaining the coefficients in a large Cl expansion is proposed. Instead of constructing and interaction matrix, the expansion coefficients are obtained directly from the list of two-electron integrals by means of an iterative procedure. At present, the method can be applied to systems with a closed-shell ground state including all singly and doubly excited configurations. The number of terms used in the expansion of the wavefunction may be as large as 10 4 – 10 5 . Wavefunctions for NH 3 with 4336 and H 2 O with 2458 configurations are presented as test cases.

B. Roos | B. Roos

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