X-ray diffraction study of CuAlS2 and CuAlSe2 at high pressures

CuA1S₂ and CuAlSe₂ are ternary compounds that cristallize in the chalcopyrite structure with body-centered tetragonal lattice of space group I4̄2d. Energy dispersive X-ray diffraction measurements up to 25 GPa were carried out on these materials at the Laboratoire pour l’Utilisation du Rayonnement Electromagnetique (LURE, Orsay, France). The experimental PV data has been fitted with a first-order Murnaghan equation of state and the values of the bulk moduli obtained are (99 ± 3) and (84 ± 2) GPa for the chalcopyrite phases of CuA1S₂ and CuAlSe₂, respectively.