Characterisation of the high-pressure structural transition and elastic properties in boron arsenic

This paper carries out the First principles calculation of the crystal structures （zinc blende （B3） and rocksalt （B1）） and phase transition of boron arsenic （BAs） based on the density-functional theory. Using the relation between enthalpy and pressure, it finds that the transition phase from the B3 structural to the B] structural occurs at the pressure of l13.42GPa. Then the elastic constants Cll, C12, C44, bulk modulus, shear modulus, Young modulus, anisotropy factor, Kleinman parameter and Poisson ratio are discussed in detail for two polymorphs of BAs. The results of the structural parameters and elastic properties in B3 structure are in good agreement with the available theoretical and experimental values.