Recent research has demonstrated that pressure affects the structure of liquids in ways that have significant geological consequences. Perhaps the most significant result is that certain silicate liquids may become denser than the surrounding mantle solids at pressures below 30 GPa. The PI will investigate the effect of pressure on the structurfe and compressibility of SiO2 liquids and glasses, and other simple silicate liquids. The proposed research includes Monte Carlo simulations of liquids with covalent and other many body pair potentials, and more efficient liquid models based on coupled integral equations. By using many body pair-potentials of several kinds will show how pressure affects loca coordination, compressibility, thermal expansivity, specific heat, etc. Emphasis will be on the identification of structural mechanisms, and their relationship to elasticity and other thermodynamic parameters; quantitatiave results may also be obtained in some cases.
