在高压下深度冷却的受限重水中存在高密度和低密度相的证据。

Evidence of the existence of the high-density and low-density phases in deeply-cooled confined heavy water under high pressures.

作者信息

Wang Zhe, Liu Kao-Hsiang, Harriger Leland, Leão Juscelino B, Chen Sow-Hsin

机构信息

Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.

National Institute of Standards and Technology Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.

出版信息

J Chem Phys. 2014 Jul 7;141(1):014501. doi: 10.1063/1.4885844.

DOI:10.1063/1.4885844

PMID:25005293

Abstract

The average density of D2O confined in a nanoporous silica matrix (MCM-41-S) is studied with neutron scattering. We find that below ~210 K, the pressure-temperature plane of the system can be divided into two regions. The average density of the confined D2O in the higher-pressure region is about 16% larger than that in the lower-pressure region. These two regions could represent the so-called "low-density liquid" and "high-density liquid" phases. The dividing line of these two regions, which could represent the associated 1st order liquid-liquid transition line, is also determined.

摘要

利用中子散射研究了限制在纳米多孔二氧化硅基质（MCM - 41 - S）中的重水（D₂O）的平均密度。我们发现，在约210 K以下，系统的压力 - 温度平面可分为两个区域。高压区域中受限D₂O的平均密度比低压区域中的约大16%。这两个区域可能代表所谓的“低密度液体”和“高密度液体”相。还确定了这两个区域的分界线，其可能代表相关的一级液 - 液转变线。