Spatially inhomogeneous bimodal inherent structure of simulated liquid water
2011 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 13, no 44, 19918-19924 p.Article in journal (Refereed) Published
In the supercooled regime at elevated pressure two forms of liquid water, high-density (HDL) and low-density (LDL), have been proposed to be separated by a coexistence line ending at a critical point, but a connection to water at ambient conditions has been lacking. Here we perform large-scale molecular dynamics simulations and demonstrate that the underlying potential energy surface gives a strictly bimodal characterization of the molecules at all temperatures and pressures, including the biologically and technologically important ambient regime, as spatially inhomogeneous either LDL- or HDL-like with a 3 : 1 predominance for HDL under ambient conditions. The Widom line in the supercooled regime, where maximal structural fluctuations take place, coincides with a 1 : 1 distribution. Although our results are based on molecular dynamics force-field simulations the close agreement with recent analyses of experimental X-ray spectroscopy and scattering data indicates a unified description also of real liquid water covering supercooled to ambient conditions.
Place, publisher, year, edition, pages
2011. Vol. 13, no 44, 19918-19924 p.
Atom and Molecular Physics and Optics Physical Chemistry
IdentifiersURN: urn:nbn:se:su:diva-71010DOI: 10.1039/c1cp22076dISI: 000296383100029OAI: oai:DiVA.org:su-71010DiVA: diva2:483621