[Raman scattering study of water up to 600 MPa at 290 K]

Raman scattering studies of the stretching band from liquid water have been conducted up to 600 MPa at 290 K. It is shown that (r1)(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(oo) under pressure. The authors conclude that, just like ice phase transition ice ( I h) --> ice(II) --> ice (V), there also probably exists water phase transition water ( I h) --> water (III) --> water (V).