X-ray photoelectron spectroscopy of CdPS3

Single CdPS3 crystals have been investigated at room temperature by means of x-ray photoemission spectroscopy (XPS) and x-ray induced Auger spectroscopy. Special attention has been paid to the Cd 3d and 4d and S and P 2p core levels and to the Cd Auger M4,5N4,5N4,5 transitions. As far as the XPS spectra are concerned, a single- peak structure has been observed for all the core levels investigated. Moreover, the Cd 4d levels are discrete and well localized, in good agreement with the transition-metal weakly interacting model according to which the transition metal-sulfur bond is weak. Further information about the nature of the cadmium-sulfur bond in CdPS3 was obtained from the calculated modified Auger parameter for Cd. A correlation has been observed between the change in the Cd modified Auger parameter in CdPS3 and the energy gap of this compound. (C) 1998 American Institute of Physics. [S0021-8979(98)10923-4].