High pressure behaviour of liquid GeO2: a molecular dynamics study

摘要

High pressure behaviour of liquid GeO2 is investigated by means of moleculardynamics simulations in the pressure range 0-20 GPa and at varioustemperatures. In agreement with the recent experiments (PRL, 92, 155506, 2004),Ge-O coordination increases under compression. For 1650 K, at ~11.5 GPa thestructure becomes 6 coordinated with a discontinuous change in the density. Thetransition from the low density liquid (LDL) to high density liquid (HDL) isfound to be reversible and the transition pressure increases with thetemperature. At lower temperatures, the low density to high density transitionis found to be continuous, but with the coexistence of two structures.