Study of melting and freezing in the Gaussian core model by molecular dynamics simulation

Abstract

Molecular dynamics calculations have been carried out to establish quantitative properties of the Gaussian core model near its crystal–fluid transition. Two densities have been considered, for both of which the stable crystal structure at absolute zero is body-centered cubic. Spontaneous melting and freezing events were observed at both densities. Annealing of defective crystalline phases and formation of amorphous ’’glassy’’ structures have been induced. Properties for the model at equilibrium display some surprising ’’waterlike’’ anomalies, including negative volume of melting, negative thermal expansion in the fluid, and increase in rate of self-diffusion as the system is compressed.