Raman spectra of ice VII phase were obtained at room temperature when the pressure was from 2.5 to 23 GPa. The experimental results indicate that the oxygen atoms distance do-o of ice decreased with pressure increasing,which results in that hydrogen bond is shortened, O--H bond is lengthened,force constant is reduced, and Raman spectra are red shifted. The orientation order of proton (hydrogen atom) is first increased and then decreased with varying the pressure, which leads to the Raman intensity increasing and then decreasing, and Raman linewidth is decreased and then increased, and the linewidth is the least when the pressure is 13 GPa.
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