Elastic Properties in High Pressure ICe•VII Phase
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چکیده
The pressure dependences of sound velocities, refractive index and elastic constants in ice-VII phase have been determined up to 8 GPa at 300 K by high-pressure Brillouin spectroscopy developed for a single molecular crystal grown in a diamond anvil cell. The Cauchy relation of C12=C44 was found at each pressure. This result suggests that the interactions between the oxygen atoms can be described by central forces, which plays one of key roles in the extreme pressure stability in the ice-VII phase. [ice-VII, Brillouin scattering, sound velocity, elastic constant, refractive index, Cauchy relation, diamond anvil cell]
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