Study of the valence bands of FePS3 and NiPS3 by resonant-photoemission spectroscopy

We have investigated the valence bands of the tiophosphates FEPS3 and NiPS3 with the resonant-photoemission technique. Some structures of the energy distribution curves show rapid intensity changes when the photon energy is scanned across the Fe or Ni 3p absorption thresholds. Instead, other structures show smooth excitation spectra. We have related the former to the transition metal ion 3d states (direct photoemission and satellites) and the latter to the (P2S6)4− states. These results support also a strongly ionic picture of these compounds.