The calculation of excited state and ground state properties of conjugated heteroatomic molecules using a single SCF-LCAO-CI method including ?-polarization

Abstract

An SCF-π method including variable π-electronegativity and σ-polarization is described and applied to the calculation of electronic transitions and ionization potentials of a large variety of heteroatomic molecules containing boron, nitrogen, oxygen, fluorine, chlorine, and sulfur. The necessary atomic parameters are the Slater effective nuclear charges and published ionization potentials, electron affinities and σ-orbital electronegativities for trigonally hybridized atoms. The program automatically adjusts the initial atomic parameters to reflect the molecular environment without the intervention of the user. The agreement between calculated and observed transition energies, oscillator strengths and ionization potentials is very good.