SCFmdash;MOmdash;LCAOmdash;CI Treatment of the Pihyphen;Electronic Structure of Formaldehyde Using Ohno's Formula for bgr;COand Constrained to Satisfy Koopmans' Theorem Exactly

摘要

The Poplemdash;Parisermdash;Parr simplification of Roothaan's matrix formulation of the Hartreemdash;Fock selfhyphen;consistenthyphen;field (SCF) equations is applied to the pihyphen;electronic portion of the formaldehyde molecule as (1) a test of the use of Ohno's resonance integral formula as a basis for obtaining selfhyphen;consistent resonance integrals for heterobonds and (2) as a test of the effect of constraining the energy of the highest occupied orbital to satisfy Koopman's theorem exactly. The calculated spectroscopic intervals, dipole moments, and charge distributions are not too far different from those obtained by the selfhyphen;consistenthyphen;electronegativity method of Brown and Heffernan, but there are indications that the present method may form a more satisfactory basis for extension to other heteroatomic conjugated systems.