Applying a new interatomic potential for the simulation of monoclinic and triclinic Li4SiO4

Abstract

An interatomic pair potential has been constructed for the simulation of α-Li4SiO4 (monoclinic phase) and γ-Li4SiO4 (triclinic phase). The potential parameters are fitted by the structure information and elastic constants. Applying this potential, the structures, mechanical properties and the vacancy formation energies are accurately calculated by the molecular static calculation methods. Additionally, a set of molecular dynamics simulations has been performed to investigate the surface energy, melting point and thermal properties such as enthalpy and specific heat capacity for two phases. We predict that the melting point of α-Li4SiO4 and γ-Li4SiO4 are 1500 K and 1300 K, respectively. The radial distribution functions are also analyzed. The present results are consistent with the experimental data and density functional theory calculation, which suggests that the potential we constructed in this work are valid and could give an accurate description to simulate the physical properties for α-Li4SiO4 and γ-Li4SiO4.