An in situ Raman spectroscopy study of subcritical and supercritical water:: The peculiarity of hydrogen bonding near the critical point
An in situ Raman spectroscopy study of subcritical and supercritical water:: The peculiarity of hydrogen bonding near the critical point
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DOI：
10.1063/1.475996
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发表时间：
1998-04-08
影响因子：
4.4
通讯作者：
Arai, M
中科院分区：
文献类型：
--
作者：
Ikushima, Y;Hatakeda, K;Arai, M
水的拉曼光谱是在高达510摄氏度的温度和高达40 MPa的压力下测量的。峰值频率随温度增加，表明氢键的断裂，并且在高于临界点的较高温度下仅略有变化。峰值频率在临界压力附近有一个最大值，在这个近临界区域内，氢键的程度随压力显著变化。最大频率Δ f相对于单体的偏差与文献NMR数据的化学位移吻合良好。氢键的程度可以从Δ f值估计。在近临界点的Δ f值显着低于那些在超或亚临界条件下，和氢键的强度减弱唯一的近临界区域。(C)1998年美国物理学会。
The Raman spectra of water are measured at temperatures up to 510 degrees C and at pressures up to 40 MPa. The peak frequency increases with temperature, indicating the break of hydrogen bonding, and it changes only slightly at higher temperatures above the critical point. The peak frequency has a maximum near the critical pressure, and the extent of hydrogen bonding significantly changes with pressure in this near-critical region. The deviation of the maximum frequency Delta f relative to that of the monomer is in good agreement with the chemical shifts with the literature NMR data. The extent of the hydrogen bonding can be estimated from the Delta f values. The Delta f values at the near-critical points are significantly lower compared with those in super-or sub-critical conditions, and the strength of the hydrogen bonding weakens uniquely in the near-critical region. (C) 1998 American Institute of Physics.