ATOMIC-SCALE STRUCTURE OF IONIC AND SEMICONDUCTING SOLID-SOLUTIONS

Experimental studies of the atomic scale structure of ionic and semiconducting solid solutions have shown that the bond-length mismatch is partially accommodated by microscopic lattice distortions and that the values of the nearest-neighbour bond lengths are intermediate between those of the corresponding pure compounds and the average Vegard value. Here we investigate theoretically the atomic scale structure of alloys using a generalized Born-Mayer model in the ionic case and an ab-initio pseudopotential approach for semiconductors. We also present results for the atomic scale structure of semiconductor heterojunctions and discuss how much interfacial and bulk strains can influence the electronic properties of the interface.