HR: 0830h
AN: V11D-0521    [PDF]
TI: Liquid Water from Linear-Scaling First-Principles Molecular Dynamics
AU: Fernandez-Serra, M
EM: mfer01@esc.cam.ac.uk
AF: Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ United Kingdom
AU: Ferlat, G
EM: gfer03@esc.cam.ac.uk
AF: Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ United Kingdom
AU: * Artacho, E
EM: emilio@esc.cam.ac.uk
AF: Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ United Kingdom
AB: The atomic-scale simulation of hydrothermal fluids in interaction with rock surfaces requires a good description of both the fluid and the chemistry at the interface. Even if empirical force-field models or hybrid schemes can offer satisfactory results in some cases, many systems of interest demand a complete first-principles description, extremely demanding from a computational point of view. A promising method for that purpose is that of linear-scaling density-functional molecular dynamics, which will be able to face the needed sizes and complexities more efficiently than traditional methods. We explore here the performance of our linear-scaling method, based on atomic orbitals of finite support, in the description of pure water in ambient conditions. Structural (pair correlation functions) and dynamical (self-diffusion, velocity autocorrelation) characteristics are obtained and compared with experiments and previous ab initio and empirical results, showing that the linear-scaling description is very satisfactory. A study of the dynamics of hydrogen bonds will be presented as well, as a characterisation of the `network-liquid' character of water, very relevant to its behaviour when interacting with surfaces or solutes, hydrophobic or hydrophilic. The first-principles description offers a quite different picture from what obtained from empirical models: hydrogen bonds live longer than expected.
DE: 3947 Surfaces and interfaces
DE: 3999 General or miscellaneous
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2003 Fall Meeting