A New Phase Transition of α-quartz GeO2 by Molecular Dynamics Simulation

Pressure - induced amorphization inα- quartz GeO2 has been investigated using constant -pressure molecular dynamics（MD）calculations with two - body potential. Interatomic potential functions of our new model are composed of Coulomb force，Short - range repulsion，van der Waals force，and Morse interactions. The calculations were carried out by an improved MD simulation program with a quantum correction（QC）. Both the static properties and crystal - to - amorphous phase transition were very well reproduced. Through an analysis of the molar volume，angular correlation functions，pair correlation functions，change of the coordination number，we predict new structural transitions forα- quartz GeO2 when pressure over 6. 0GPa at room temperature，the new phase comprise mixed arrays of fourfold（33%）and sixfold（66%）Ge - O coordination.