First-principles study of hydronitrogen compounds: Molecular crystalline NH4N3 and N2H5N3

The structural, elastic, mechanical, electronic properties, formation energy and cohesive energy of orthorhombic NH4N3 and monoclinic N2H5N3 are studied by the plane-wave method based on the first-principles density functional theory. The calculated results of two compounds are in agreement with the available values. The orthorhombic NH4N3 is more energetically stable. The independent elastic constants, bulk modulus, shear modulus, Young’s modulus and Poisson’s ratio of two compounds have been investigated. The electronic band structures, density of states and charge density distributions of orthorhombic NH4N3 and monoclinic N2H5N3 have been analysed to understand electronic properties and chemical bonding.