Anisotropic ideal strengths and chemical bonding of wurtzite BN in comparison to zincblende BN

The ideal strengths, electronic density of states, and charge density difference of wurtzite w-BN had been calculated by ab initio density functional theory and compared to zincblende c-BN. Both polymorphs show a different stacking of lattice planes but have comparable anisotropic strengths, which are due to the similar bonding of three-dimensional sp(3) covalent networks, comparable bond lengths, and charge transfer between the boron and nitrogen atoms.