Molecular-field splitting in S2p photoelectron spectra of dimethyl sulfide and sulfur dichloride

High-resolution S2p photoelectron spectra have been measured for sulfur dichloride and dimethyl sulfide. By means of efficient fitting procedures and theoretical analyses, the vibrational fine structure has been disentangled from the molecular-field induced splitting of the S2p3/2 core-ionized level. The resulting molecular-field splitting is determined to be 177 meV in the case of SCl2 and 104 meV for (CH3)2S. Ab initio calculations that include core–valence electron correlation are able to reproduce these values to within 3 meV. Theoretical predictions of the molecular-field splitting are presented for a series of related sulfur compounds, SX2, where X=H, NH2, CN, and F.