corner
corner
APS » Journals » Phys. Rev. Lett. » Volume 89 » Issue 24
< Previous Article | Next Article >

Phys. Rev. Lett. 89, 245504 (2002) [4 pages]

Pressure-Induced Structural Changes in Liquid SiO2 from Ab Initio Simulations

Download: PDF (112 kB) Buy this article Export: BibTeX or EndNote (RIS)

Andrea Trave1,2, Paul Tangney1,2,3, Sandro Scandolo1,2,3, Alfredo Pasquarello4,5, and Roberto Car1
1Department of Chemistry and Princeton Materials Institute, Princeton University, Princeton New Jersey 08544
2Department of Geosciences, Princeton University, Princeton New Jersey 08544
3International School for Advanced Studies (SISSA) and INFM / Democritos, National Simulation Center, I-34014 Trieste, Italy
4Institut de Théorie des Phénomènes Physiques (ITP), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
5Institut Romand de Recherche Numérique en Physique des Matériaux (IRRMA), CH-1015 Lausanne, Switzerland

Received 1 February 2002; published 25 November 2002

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.

© 2002 The American Physical Society

URL:
http://link.aps.org/doi/10.1103/PhysRevLett.89.245504
DOI:
10.1103/PhysRevLett.89.245504
PACS:
62.50.+p, 61.20.–p, 71.15.Pd, 91.60.Gf
 
< Previous Article | Next Article >