title: Pressure-induced structural changes in liquid SiO2 from Ab initio simulations.
abstract: First-principles molecular dynamics simulations at constant pressure have been used to investigate the mechanisms of compression of liquid SiO2. Liquid SiO2 is found to become denser than quartz at a pressure of about 6 GPa, in agreement with extrapolations of lower pressure experimental data. The high compressibility of the liquid is traced to medium-range changes in the topology of the atomic network. These changes consist in an increase of network connectivity caused by the pressure-induced appearance of coordination defects.
authors.affiliation: Department of Chemistry and Princeton Materials Institute, Princeton University, New Jersey 08544, USA.
authors.forename: Andrea
authors.initials: A
authors.lastname: Trave
authors.forename: Paul
authors.initials: P
authors.lastname: Tangney
authors.forename: Sandro
authors.initials: S
authors.lastname: Scandolo
authors.forename: Alfredo
authors.initials: A
authors.lastname: Pasquarello
authors.forename: Roberto
authors.initials: R
authors.lastname: Car