RESONANT 2P-]3D PHOTOEMISSION MEASUREMENT OF MPS(3) (M=MN, FE, NI)

Resonant 2p --> 3d photoemission (RPE) spectra in the valence band reg ion of the transition-metal thiophosphates MPS(3) (M = Mn, Fe, Ni) hav e been measured by using synchrotron radiation. These spectra show lar gely enhanced resonated profiles and spread over in the wide range (si milar to 15 eV) at the incident photon energy of the transition-metal 2p(3/2) absorption peak. Comparing the obtained spectra with the resul t of the cluster calculation of RPE spectra for transition-metal monox ides carried out by Tanaka and Jo, we argued the differences of the tw o parameters, charge transfer energy Delta and d-d Coulomb interaction energy U-dd of these materials. It is suggested that MnPS3 and FePS3 are Mott-Hubbard type insulator with Delta > U-dd, while NiPS3 is a ch arge transfer type insulator with Delta < U-dd.