title: Structure of a new dense amorphous ice.
abstract: The detailed structure of a new dense amorphous ice, VHDA, is determined by isotope substitution neutron diffraction. Its structure is characterized by a doubled occupancy of the stabilizing interstitial location that was found in high density amorphous ice, HDA. As would be expected for a thermally activated unlocking of the stabilizing "interstitial," the transition from VHDA to LDA (low-density amorphous ice) is very sharp. Although its higher density makes VHDA a better candidate than HDA for a physical manifestation of the second putative liquid phase of water, as for the HDA case, the VHDA to LDA transition also appears to be kinetically controlled.
authors.affiliation: Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: J L
authors.initials: JL
authors.lastname: Finney
authors.forename: D T
authors.initials: DT
authors.lastname: Bowron
authors.forename: A K
authors.initials: AK
authors.lastname: Soper
authors.forename: T
authors.initials: T
authors.lastname: Loerting
authors.forename: E
authors.initials: E
authors.lastname: Mayer
authors.forename: A
authors.initials: A
authors.lastname: Hallbrucker