290K下0.1～600MPa水的Raman光谱原位研究

Abstract

在290 K和0.01～600 MPa条件下, 就压力对液态水对称伸缩振动的影响进行了原位Raman散射光谱研究. 表明: (1)在0.1～200 MPa范围内, (ν1)max随着压力升高而减小; (2)在200～400 MPa范围内, 压力升高导致(ν1)max增大, 并在400 MPa时达到最大值; (3) (ν1)max随着压力的进一步升高(>400 MPa)而降低. 这表明在200和400 MPa时, 液态水结构的变化是不连续的, 这也与在该压力范围内rOO的变化特征是一致的. 可认为与冰Ⅰh→冰Ⅲ→冰Ⅴ的相变相类似, 也许存在液态水Ⅰh→水Ⅲ→水Ⅴ的相变.

Raman scattering studies of the stretching band from liquid water have been conducted up to 600 MPa at 290 K. It is shown that (nu(1))(max) decreases with increasing pressure initially and reaches the minimum at about 200 MPa, and increases at higher pressure up to about 400 MPa, then decreases with increasing pressure up to 600 MPa. And this is also in accordance with the behavior of r(infinity) under pressure. The authors conclude that, just like ice phase transition ice (I h)-->ice(III)-->ice(V) there also probably exists water phase transition water (I h)-->water(III)-->water(V).