Low compressible β-BP3N6

Using first principles calculation, the structural and mechanical properties of β-BP3N6, which adopts an orthorhombic structure with space group Pna21 (no. 33), were determined at three different pressure values (0, 20, and 42.4 GPa). The nine independent elastic constants meet all necessary and sufficient conditions for mechanical stability criteria for an orthorhombic crystal. β-BP3N6 shows strong resistance to volume change and hence a potential low compressible material. The Vickers hardness of β-BP3N6 was found to range between 49 and 51 GPa for different external pressures imposed on the crystal. These high values of Vickers hardness imply that β-BP3N6 is a potential superhard material.