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Half-Projected and Projected Hartree-Fock Calculations for Singlet Ground States. i. four-Electron Atomic Systems

✍ Scribed by Yves G. Smeyers; L. Doreste-Suarez

Publisher
John Wiley and Sons
Year
1973
Tongue
English
Weight
552 KB
Volume
7
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

The half‐projected Hartree‐Fock function (HPHF) for singlet states is defined as a linear combination of two Slater determinants, which contains only spin eigenfunctions with even quantum number. Using a self‐consistent procedure based on the generalized Brillouin's theorem, the RHF, HPHF and PHF functions are deduced for the ground states of the Li^−^, Be, B^+^, and C^2+^ systems, in a limited basis set. It is found that the HPHF function yields better energy values than the RHF function, very close to that of the PHF one. The HPHF scheme seems thus to be useful as a substitute for the PHF model, specially in the case of large electronic systems in which the latter method becomes unmanageable.

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