title: Density hysteresis of heavy water confined in a nanoporous silica matrix.
abstract: A neutron scattering technique was developed to measure the density of heavy water confined in a nanoporous silica matrix in a temperature-pressure range, from 300 to 130 K and from 1 to 2,900 bars, where bulk water will crystalize. We observed a prominent hysteresis phenomenon in the measured density profiles between warming and cooling scans above 1,000 bars. We interpret this hysteresis phenomenon as support (although not a proof) of the hypothetical existence of a first-order liquid-liquid phase transition of water that would exist in the macroscopic system if crystallization could be avoided in the relevant phase region. Moreover, the density data we obtained for the confined heavy water under these conditions are valuable to large communities in biology and earth and planetary sciences interested in phenomena in which nanometer-sized water layers are involved.
authors: Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors: Yang
authors: Y
authors: Zhang
authors: Antonio
authors: A
authors: Faraone
authors: William A
authors: WA
authors: Kamitakahara
authors: Kao-Hsiang
authors: KH
authors: Liu
authors: Chung-Yuan
authors: CY
authors: Mou
authors: Juscelino B
authors: JB
authors: Leão
authors: Sung
authors: S
authors: Chang
authors: Sow-Hsin
authors: SH
authors: Chen