Molecular dynamics simulation of high-pressure densification of fluorozirconate glass

Abstract Molecular dynamics simulations have been performed for a fluorozirconate glass and its model crystals in order to investigate the mechanism of the peculiar high-pressure densification phenomenon of the glass. All the polymorphs and the pressure-induced phase-transition of the model crystals were satisfactorily reproduced. The changes in the density, the F − coordination number and the connectivity of ZrF n polyhedra during the compression–decompression process are investigated under the glassy state. The density increases under high pressure, accompanying the increases in the coordination number and the connectivity. The effect of annealing treatment near T g is also investigated. The effect was significant around 20 GPa, around which a maximum was found in the treatment-pressure dependence of density after decompression, only for the samples with the annealing treatment before decompression.