In this paper we present a highly convergent renormalization scheme for the computation of Green's functions of interfaces in the case of tight-binding models. It allows the calculation of the Green's function of the whole infinite system, which is built up of a stack of a semi-infinite solid of material A, an interface region, and a semi-infinite solid of material B. As a first application we analyse the layer-resolved interface electronic structure of Sb/GaAs(110) and compare the results with calculations for (xML)Sb/GaAs(110), x=1,2 and 3. We find several interface states in the fundamental band gap of GaAs(110). Their energy dispersion and orbital composition are discussed in detail. Furthermore, we find that the interface electronic structure of (3ML)Sb/GaAs(110) still differs significantly from that of the system terminated by a semi-infinite Sb crystal.

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Based on a recently proposed localization procedure, a nonlocal pseudopotential scheme is derived to calculate potential coefficients V G ជ G ជ Ј (k ជ ) which can be decomposed into terms, each being quadratic in k ជ and multiplied by a function of (G ជ ϪG ជ Ј), thus making them applicable to some important cases where local potential coefficients are required. Electronic structure calculations for semiconductors are in agreement with well-known semiempirical local pseudopotential band structures, as shown for GaAs. Nevertheless, the potential may significantly deviate from the semiempirical results. In order to test wave functions and transition probabilities, we prove the success of the procedure in a more troublesome case, i.e., applying it to a transitionmetal compound as the experimentally well-investigated layered crystal TiSe 2 , which up to now was not treated with a pseudopotential. Photoemission spectra within the one-step model are presented using Pendry's method of complex band-structure calculation. The latter formalism had to be slightly generalized for the quasilocal properties of the potential. The agreement of the spectra with experimental data shows this method to be a reliable and practical tool to use nonlocal pseudopotentials for conduction-band wave functions of electron spectroscopies.

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