Chalcopyrite polymorph for superhard BC2N

Abstract

A chalcopyrite structure is predicted for the potential superhard boron-carbonitride (BC2N), based on ab initio pseudopotential density functional method. Lattice constant, formation energy, bulk modulus, band structure, and electron density of states are calculated. The results show that this compound is a wide gap semiconductor with a direct band gap of about 3.3eV. The calculated Vickers hardness is about 72GPa, which is very close to the measured hardness of c-BC2N (76±4GPa).