VALENCE-BAND STRUCTURES OF TITANIUM NITRIDE AND TITANIUM CARBIDE CALCULATED WITH CHEMICALLY COMPLETE CLUSTERS

Valence band structures of TiN and TiC have been calculated by the DV- X, cluster method. A chemically complete duster TrX6Ti12Ti6 (X = N or C) is used to improve termination of the cluster and electroneutrality of the Ti-N and Ti-C stoichiometric pairs. Density of states for the valence band, theoretical Ti L-3, Ti K and X K x-ray emission spectra for TiN and TiC are presented and are in good agreement with the exper imental ones. Interaction between the metal and non-metal atoms is dis cussed. Experimental Ti L3 x-ray emission spectra for TiN and TiC have also been obtained in the present work, using monochromatized synchro tron radiation.