Computer Simulation of Noncrystalline P2O5 , an Ionic–Covalent Oxide

Abstract

The semiclassical molecular dynamics simulation method proposed earlier for studying ionic–covalent oxide systems was applied to noncrystalline P2O5 . The expressions for the potentials of ionic–covalent bonds were found. The internal energy comprises the contributions from the ionization energy of phosphorus, electron affinity of oxygen, Coulombic interaction, repulsion between ionic shells, and covalent interaction. The ionic charges were computed by minimizing the potential energy at each simulation step. Taking into account mixed bonding improves agreement with the experimental data on the density, energy, and structure of condensed P2O5 . The bond ionicity in glassy P2O5is about 68%. The proposed potentials are shown to be suitable for computing a number of properties of isolated P4O10molecules.