High-resolution photoelectron spectra for the 2p electrons in H2S, SO2, CS2, and OCS show the effects of vibrational excitation in the core-excited species as well as the splitting of the 2p(3/2) hole state by the molecular field. Theoretical calculations at the Hartree-Fock level account reasonably well for the vibrational structure. The molecular-field splitting is calculated with a configuration interaction-based method using large basis sets. This produces values for the 2p(3/2) splitting of 108, 96, 129, and 144 meV for the title molecules, to be compared with experimental values of 110, 105, 140, and 150 meV. Thus all observed features in the spectra are quantitatively accounted for by theoretical modeling.