Bond lengths around isovalent impurities and in semiconductor solid solutions

Abstract

Using a valence force field, we predict the symmetric lattice distortions around isovalent impurities in 64 semiconductor-impurity systems. For the five systems for which extended x-ray absorption fine-structure (EXAFS) data are available, the results are in excellent agreement with experiment. Our theory also explains quantitatively, without adjustable parameters, the observed bond-length variations in solid solutions $A_{1-x}{B}_{x}C$ of semiconductor alloys, as well as their excess enthalpies of mixing.