First-Principles Study of the Elastic Properties of Nitrates

Elastic properties of nitrates LiNO3, NaNO3, KNO3 and NH4NO3 are studied from first principles in gradient approximation of the density functional theory by method of linear combination of atomic orbitals using CRYSTAL software complex. Elastic constants and modules, hardness, Poisson coefficient, and anisotropy parameters are calculated. Sound velocity, Debye temperature, thermal conductivity and Gruneisen parameter are evaluated. Mechanical stability, anisotropy and the series dependencies are shown for the examined compounds. Strong elastic anisotropy indicates anisotropy of interatomic interactions. The elastic constants are in good agreement with available experimental data.