冲击加载下液态水的结构相变

Structural transformation of liquid water under shock compression condition

在一级轻气炮上,利用冲击波加载技术结合光透射测量技术获得了水在1—1.6 GPa压力范围内的透射光谱.结果表明,透射光变化是由于在冲击压缩过程中,液态水结构在P=0.9 GPa左右存在的不连续引起的,与文献报道结果一致.结合热力学计算结果和水的相图表明,该变化可能是压力导致液态水由低密度到高密度态的转变所致.实验为在线研究液态水和其他分子液体的结构相变提供了新的途径和方法.

Using shock wave loading and real time optical transmission measurements, the transmission spectra of liquid water compressed between the quartz windows under pressures in a range of 1-1.6 GPa are obtained. A discontinuity of liquid water at nearly 0.9 GPa during the shock is observed. Combining the phase diagram of water with calculation results, it is suggested that the discontinuity of liquid water is due to a possible phase transition from low density water to high density water under the experimental conditions. The method can also be used to study other transparent molecular liquids in shock compression experiments.