“Optical absorption spectra of some transition metal thiophosphates”

Near-infrared and visible absorption spectra at room temperature of MnPS3, CoPS3, CoPS3 are reported. These materials show weak structures below their fundamental absorption thresholds, due to the 3d-3d transitions occurring on the transition metal ion. By comparison with other transition metal compounds, such excitations are interpreted on the basis of the ligand field theory. The appearance of well developed crystal field spectra is a further confirmation that these materials are considerably ionic.