Elastic properties of cubic K2B12H12 from theoretical calculations

The elastic and mechanical properties of the cubic Fm (3) over bar K2B12H12 have been carried out based on first-principles calculations and elastic theory. The optimized structural parameters are in good agreement with available experimental and theoretical data. A serial of physical parameters are predicted for the first time, such as the single independent crystal elastic constants, polycrystalline elastic moduli, linear compressibility, and so on. It is found that the cubic Fm (3) over bar K2B12H12 is mechanically stable and ductile at zero temperature and zero pressure. The calculated anisotropic factors, directional dependent Young's modulus and Poisson's ratio varied with orientation show that the cubic Fm (3) over bar K2B12H12 is a rather weak anisotropy in its elastic behavior. In addition, the Debye temperature, average elastic wave velocity, as well as sound velocity in [100], [110] and [111] directions are also calculated. (C) 2016 Elsevier B.V. All rights reserved.