Morse Stretch Potential Charge Equilibrium Force Field for Ceramics: Application to the Quartz-Stishovite Phase Transition and to Silica Glass
نویسندگان
چکیده
To predict phase transitions in ceramics and minerals from molecular dynamics simulations, we have developed a force field in which the charges are allowed to readjust instantaneously to the atomic configurations. These charges are calculated using the charge equilibration (QEq) method. In addition to electrostatics, a two-body Morse stretch potential is included to account for shortrange nonelectrostatic interactions. This MS-Q potential is applied herein to SiO2, where we find that it describes well the fourfold coordinated and sixfold coordinated systems (such as quartz and stishovite), silica glass, and the pressure-induced phase transition from quartz to stishovite. [S0031-9007(99)08499-9]
منابع مشابه
The Ms-q Force Field for Ceramics; Application to the Quartz- Stishovite Phase Transition and to Silica Glass
In order to predict phase transitions in ceramics and minerals from molecular dynamics (MD) simulations, we have developed a new strategy for force elds in which the charges are allowed to readjust instantaneously to the atomic conngurations. These charges are calculated using the charge equilibration (QEq) method. In addition to electrostatics, a two-body Morse stretch potential is included to...
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