Elastic Properties of single Crystalline Methane and carbon Bioxide Hydrates

甲烷水合物（MH）是一种冰状化合物，是一种重要的未来能源和温室气体，利用金刚石压砧装置原位测量了MH的声速、绝热弹性模量、体积模量、弹性各向异性、和Cauchy违反单晶甲烷水合物在压力高达0.6 Gpa和296 K.声速显示出几乎各向同性的行为相对于晶体取向，和轻微的TA模式软化与压力意味着MH的结构变得不太稳定，对剪切分量在高压下。弹性模量和体积模量表明，MH的压缩性略大于冰Ih。这些新的结果对天然气水合物（MH）作为未来能源的应用和抑制全球变暖具有重要意义。

Methane hydrate (MH) is an ice-like compound, and becomes an important material with respect to both a substantial future energy resource and a powerful greenhouse gas contributing to the global warming.By using in situ high-pressure Brillouin spectroscopy in a diamond-anvil cell, we have determined the pressure dependence of acoustic velocities, adiabatic elastic moduli, bulk modulus, elastic anisotropy, and Cauchy violation of single-crystal methane hydrate at pressures up to 0.6 Gpa and 296 K.Acoustic velocities show nearly isotropic behaviors with respect to the crystal orientation, and the slight TA-mode softening with pressure implies that the structure of MH is becoming less stable against the shear component under high pressures. Elastic moduli and bulk modulus indicate that MH is slightly more compressible than ice I_h.These new results are important and available to apply gas hydrates (MH) on a future energy resource and to suppress the global warming.