First-principles calculations on elasticity of OsN2 under pressure

First-principles calculations of the crystal structure and the elastic properties of OsN2 have been carried out with the plane-wave pseudopotential density functional theory method. The calculated values are in very good agreement with experimental data as well as with some of the existing model calculations. The dependence of the elastic constants c(ij), the aggregate elastic moduli (B, G, E), Poisson's ratio, and the elastic anisotropy on pressure has been investigated. Moreover, the variation of the Debye temperature and the compressional and shear elastic wave velocities with pressure P up to 60 GPa at 0 K have been investigated for the first time. (C) 2009 Elsevier Ltd. All rights reserved.