Ab initio elasticity of chalcopyrites

A critical review of the experimental data of elastic stiffness constants of AgGaX2 and CuInX2 (X=S,Se) chalcopyrites is given. Using the ab initio pseudopotential method, their elastic constants have been calculated from strain-energy and from strain-stress relationships. On the basis of the linear elasticity approximation, axial and total compressibilities as well as elastic anisotropy factors have been derived. The calculated results are compared with available experimental data and previous calculations based on phenomenological models. (C) 2003 American Institute of Physics.