Electronic and elastic properties of Li3N under different pressure

The electronic structures and elastic properties of lithium nitride are studied using first-principles calculations. The energy band structure and density of state (DOS) of Li3N at 0 GPa are calculated. The band gap energy of Li3N versus the pressure 0–38.8 GPa is obtained. We find that the band gap energy decreases as the pressure increases. The geometry optimized structural parameters for lithium nitride under different pressures are listed. The parameters a, c, and E all decrease with increasing pressure. However, parameter B, S and Y increase with pressure. The normalized lattice constants and the elastic modulus as two functions of pressure from 0 to 38.8 GPa are obtained. All the calculated elastic constants Cij increase by different rates with increasing pressure.