Dynamical Crossover in Hot Dense Water: The Hydrogen Bond Role.
Dynamical Crossover in Hot Dense Water: The Hydrogen Bond Role.
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热浓水中的动态交叉：氢键作用。
DOI：
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发表时间：
2016
影响因子：
3.3
通讯作者：
L. Bove
中科院分区：
文献类型：
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作者：
Umbertoluca Ranieri;P. Giura;F. Gorelli;M. Santoro;S. Klotz;P. Gillet;L. Paolasini;M. Koza;L. Bove
我们调查的太赫兹动力学液体H2O作为压力的函数沿着450 K等温线，耦合准弹性中子散射和非弹性X射线散射实验。单分子动力学的压力依赖性在微观平移和旋转方面都是反常的。特别是，斯托克斯-爱因斯坦-德拜方程被证明是违反热水压缩到GPa制度。氢键网络的动力学仅受压力变化的微弱影响。驱动集体动力学的结构弛豫的时间尺度仅增加了沿着的调查等温线的2倍，和结构弛豫强度原来几乎是压力无关的。我们的研究结果点在持久性的氢键网络在热稠密的水冰VII结晶，从而质疑长期以来的看法，即氢键在液态水的压缩作用下被打破。
We investigate the terahertz dynamics of liquid H2O as a function of pressure along the 450 K isotherm, by coupled quasielastic neutron scattering and inelastic X-ray scattering experiments. The pressure dependence of the single-molecule dynamics is anomalous in terms of both microscopic translation and rotation. In particular, the Stokes-Einstein-Debye equations are shown to be violated in hot water compressed to the GPa regime. The dynamics of the hydrogen bond network is only weakly affected by the pressure variation. The time scale of the structural relaxation driving the collective dynamics increases by a mere factor of 2 along the investigated isotherm, and the structural relaxation strength turns out to be almost pressure independent. Our results point at the persistence of the hydrogen bond network in hot dense water up to ice VII crystallization, thus questioning the long-standing perception that hydrogen bonds are broken in liquid water under the effect of compression.
影响因子：
8.6
作者：
C. Drechsel-Grau;D. Marx
通讯作者：
C. Drechsel-Grau;D. Marx