First-principles study of atomic nitrogen solid with cubic gauche structure

Recently, Eremets et al. reported high-pressure synthesis of an allotropic form of nitrogen with the theoretically predicted cubic gauche (cg) structure [M.I. Eremets, et al., Nature Mater. 3 (2004) 558]. Here the structural and physical properties of cg-N solid under high pressure have been investigated using first-principles density functional theory. The bulk modulus and elastic constants of cg-N solid were calculated. The pressure-induced changes of lattice constant, bond length, electronic band gap, and vibrational frequencies were computed and compared with available experiments.