Non-empirical valence-electron molecular orbital calculations: spin-orbit splitting in the ion states of the tin and antimony halides

Abstract

The non-empirical valence-electron (NEVE) molecular orbital method can accommodate molecules containing p-block atoms up to the fourth row in a minimum STO basis calculation. Unlike many MO methods in current use, the NEVE method allows comparisons down the Periodic Table. The present study illustrates this for the tin tetrahalides and antimony trihalides. The calculated orbital eigenvalues correlate well with the photoelectron spectra of these compounds, and by using a semi-empirical spin-orbit hamiltonian theoretical spin-orbit splitting patterns are obtained. The calculated splittings are generally smaller for the antimony trihalides, and a revised assignment of the photoelectron spectrum of antimony tri iodide is suggested.