Koster-Slater model for the interface-state problem

A Koster-Slater approach to the problem of localized states at semiconducto r interfaces has been developed. It allows us to relate the existence and/o r the energy position of interface states to some essential bulk features o f the constituent materials and some interface-bonding parameters. The cond ition for the existence of localized states and the relevance of the model will be discussed comparing the predictions entailed by the latter with the results of ab initio calculations on the Ge/GaAs (110) interface.