A double expansion method for calculating molecular properties: III. Screening in one and two-electron diatomie molecules

C. D.H. Chisholm, K. B. Lodge

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We have extended a form of double perturbation theory for molecules by including a screening constant in the calculation. We have computed the ground state energies for the diatomic systems H2+, HHe2+, H2 and HHe+ with inclusion of screening. A comparison of the results with those in the unscreened approximation is interesting. Thus for the one-electron systems the energies up to second order are better if we do not include screening. However, for the two-electron systems the energies up to second order are improved by screening except at small internuclear separation.

Original languageEnglish (US)
Pages (from-to)673-680
Number of pages8
JournalMolecular Physics
Issue number4
StatePublished - Jan 1 1971


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