HR: 11:05h
AN: V21E-04 INVITED     [PDF]
TI: Spectroscopic and thermal properties of minerals from density-functional perturbation theory
AU: * Refson, K
EM: k.refson@rl.ac.uk
AF: CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX United Kingdom
AB: Ab-initio calculations based on density-functional theory have provento give a highly accurate description of structural and elastic properties of minerals under pressure. To evaluate spectroscopic, dielectric and thermal properties it is necessary to compute the second derivatives of the energy with respect to a displacement or electric field perturbation. While the Hellman-Feynmann theorem makes the computation of forces (first derivatives of the energy) straightforward, second derivatives depend on the linear response of the orbitals and density to the perturbation. I will sketch the variational formulation of density-function perturbation theory, and it's implementation in the CASTEP plane-wave code. The capabilities will be illustrated with calculation of the full phonon dispersion spectra and dielectric properties of a-quartz, ZrO$_2$ and NaHF$_2$.
DE: 3909 Elasticity and anelasticity
DE: 3919 Equations of state
DE: 3924 High-pressure behavior
DE: 3949 Thermal expansivity
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting