title: Topological defects and bulk melting of hexagonal ice.
abstract: We use classical molecular dynamics combined with the recently developed metadynamics method [Laio, A.; Parrinello, M. Proc. Natl. Acad. Sci. U.S.A. 2002, 99, 20] to study the process of bulk melting in hexagonal ice. Our simulations show that bulk melting is mediated by the formation of topological defects which preserve the coordination of the tetrahedral network. Such defects cluster to form a defective region involving about 50 molecules with a surprisingly long lifetime. The subsequent formation of coordination defects triggers the transition to the liquid state.
authors.affiliation: Computational Science, Department of Chemistry and Applied Biosciences, ETH Zürich, USI Campus, Via Buffi 13, CH-6900 Lugano, Switzerland. ddonadio@phys.chem.ethz.ch
authors.forename: Davide
authors.initials: D
authors.lastname: Donadio
authors.forename: Paolo
authors.initials: P
authors.lastname: Raiteri
authors.forename: Michele
authors.initials: M
authors.lastname: Parrinello
mesh_terms: D007053:Ice; D008433:Mathematics; D015394:Molecular Structure; D013816:Thermodynamics; D014867:Water / Q000737:chemistry*
chemical_list: D007053:Ice; D014867:Water