First-principles study of wurtzite BC2N

The structural, electronic, and mechanical properties have been calculated by using first-principles pseudopotential density functional method for three possible configurations of wurtzite BC2N, which are deduced from four-atom wurtzite boron nitride unit cell. Our results show that the BC2N-w3 with the maximum C-C and B-N bonds has the lowest total energy among all the reported sp(3)-bonded BC2N structures. Energetically, the wurtzite structure is more stable than the zinc-blende structure for the sp(3)-bonded BC2N, which is different from sp(3)-bonded carbon and boron nitride. The present BC2N-w3 has the highest density, the largest bulk and shear moduli, the largest band gap, and the largest Vickers hardness among all the investigated sp(3)-bonded BC2N structures. The phase stability of BC2N-w3 indicates that it should be experimentally synthesized more easily than the zinc-blende-structured BC2N.