First-principles investigations on electronic and elastic properties of YX (X = N, P, As and Sb) under high pressure

An investigation on electronic and elastic properties of YX (X = N, P, As and Sb) under high pressure is conducted using first-principles calculations based on density functional theory (DFT) with the plane wave basis set as implemented in the CASTEP code. Our results demonstrate that the sequence of the pressure-induced phase transition of these compounds is from the NaCl-type (B1) to the CsCl-type (B2) structure. The calculated lattice constants, bulk modulus and transition pressures are reported, which are in good agreement with the available experimental results and the previous theoretical data. In addition, Debye temperatures of these compounds are determined for the first time.