HR: 1340h
AN: MR13A-0051    [Abstracts]
TI: First Principles Molecular Dynamics Simulations of Diopside Liquid
AU: * Sun, N
EM: nsun@umich.edu
AU: Stixrude, L
EM: stixrude@umich.edu
AB: Diopside is an important component of basalt and knowledge of its properties provides crucial understandings on igneous processes, and planetary evolution. The diopside melting curve, which has been measured to 16 GPa (Gasparik, 1996), has been found to have a negative Clapeyron slope when pressure is greater than 14 GPa. Therefore, the liquid-crystal density contrast of diopside may display an inversion and the liquid-crystal density contrast is expected to decrease as pressure increases. One possible reason is pressure-induced changes in the Si-O coordination number of the liquid. We will apply density functional theory to the study of diopside liquids via first principles molecular dynamics, which will allow us to examine the origin of the pressure-induced decrease in the liquid-crystal density contrast in terms of the structure and bonding of the liquid. We will also compare with experiments and analyze the equation of state of diopside. We anticipate that this study will be also helpful to have a broader understanding of silicate liquid structure at high pressure.
DE: 3919 Equations of state
DE: 3924 High-pressure behavior
SC: Mineral and Rock Physics [MR]
MN: Fall Meeting 2005