Chemical bonding and charge redistribution: Valence band and core level correlations for the Ni/Si, Pd/Si, and Pt/Si systems

Via a systematic study of the correlation between the core and valence level x-ray photoemission spectra, the nature of the chemical bonding and charge redistribution for bulk transition metal silicides has been examined. Particular emphasis is placed on Pt2Si and PtSi. It is observed that the strength of the metal (d)–silicon ( p) interaction increases in the order Ni2Si<Pd2Si<Pt2Si. It is also observed that both the metal and silicon core lines shift to higher binding energy as the silicides are formed. The notion of charge redistribution for metallic bonds is invoked to explain these data.