论文标题
两个组件动力学和超临界水中的液体状态跨界
Two-component dynamics and the liquid-like to gas-like crossover in supercritical water
论文作者
论文摘要
通过非弹性X射线散射和分子动力学模拟，研究了子至超临界水中的分子尺度动力学。所获得的纵向电流相关光谱可以分解为两个主要组成部分：低频（LF），气体样成分和高频（HF）成分（HF）成分，由O-O伸展分子之间的O-O伸展模式产生，回想起在气压水中延长较长的声学模式。随着温度的升高，氢键网络会减小，光谱重量从HF转移到LF，从而导致从液体样到气体样动力学的过渡，并且在Widom线周围迅速变化。
Molecular-scale dynamics in sub- to super-critical water is studied with inelastic X-ray scattering and molecular dynamics simulations. The obtained longitudinal current correlation spectra can be decomposed into two main components: a low-frequency (LF), gas-like component and a high-frequency (HF) component arising from the O--O stretching mode between hydrogen-bonded molecules, reminiscent of the longitudinal acoustic mode in ambient water. With increasing temperature, the hydrogen-bond network diminishes and the spectral weight shifts from HF to LF, leading to a transition from liquid-like to gas-like dynamics with rapid changes around the Widom line.
