Electronic and mechanical properties, phase stability, and formation energies of point defects of niobium boronitride Nb$_{2}$BN

The electronic structure, Fermi surface, Sommerfeld and Pauli paramagnetic susceptibility coefficients, cohesive energies, phase and point defect formation energies, elastic constants, bulk, shear, and Young moduli, Poisson ratios, and Vickers microhardness of niobium boronitride Nb$_{2}$BN are determined by the ab initio FLAPW-GGA full-potential method. The obtained values are discussed in comparison with similar data for Mo$_2$BC and other related binary carbides, nitrides, and borides of transition metals, and with available experimental data.