Proving coexistence of ice‐like and quartz‐like structure in localized liquid water by stimulated Raman scattering

Abstract

Liquid water is a complex system consisting of ice‐like and quartz‐like structure based on the classic two‐state model. Although lots of theoretical work have been developed about this model, the experimental evidences are still needed. Herein, a 355‐nm pulse laser is employed to excite stimulated Raman scattering (SRS) of liquid water both in bulk and on surface, with the generation of shockwave‐induced dynamic high pressure. Two characteristic features Raman peaks of both spontaneous Raman and SRS indicate the coexistence of two structures in localized water area. The ice‐like structure corresponds to ice Ih phase under the presented conditions, because the pressure dependence behavior of Raman shift agree well with the anomaly of diffusion coefficient of ice Ih phase, when the shock wave‐induced dynamic high pressure forms. Two structures show different pressure‐dependent behaviors based on the SRS results; meanwhile, the distribution of two structures is different in bulk and on surface water.

Recent advances in linear and nonlinear Raman spectroscopy. Part XIV

“…The two structures show different pressure‐dependent behaviors based on the SRS results; meanwhile, the distribution of two structures is different in the bulk and on the surface of water. Wang et al [ 112 ] described ozone‐induced hydrogen bond water networks that were enhanced in stimulated Raman scattering. Simultaneously, stimulated Raman scattering lines indicate that a high‐pressure ice‐phase is formed in mixture solutions which is attributed to the reduction of the laser breakdown threshold of liquid water by ozone, resulting in a strong dynamic high pressure.…”