First-Principles Interatomic Potential of Silica Applied to Molecular Dynamics

A new method to provide interatomic pair potentials from ab initio Hartree-Fock self-consistent-field calculations is proposed; potentials are calculated for model clusters of silica (Si${\mathrm{O}}_2$). They are tested in the molecular-dynamics simulation of crystalline states, in which four known polymorphs of silica are shown to be dynamically stable.