Prediction study of structural and elastic properties under pressure effect of CdX2O4 (X = Al, Ga, In) spinel oxides

First principle calculations of structural and elastic properties of CdAl2O4, CdGa2O4 and CdIn2O4 compounds are presented, using the pseudo-potential plane-waves approach based on density functional theory, within the generalized gradient approximation GGA. The lattice constants and internal parameters are in good agreement with the available experimental results. Young modulus, Poisson ratio, bulk modulus, elastic constants and their pressure dependence are also calculated. Since, the elastic constants and their pressure derivatives of these compounds have not yet been established theoretically or experimentally, our results can serve as a prediction for future investigations. (C) 2006 Elsevier B.V. All rights reserved.