| 摘 要： | High-pressure Raman studies at room temperature are performed on CC14 up to 13 GPa. The Raman bands of the internal modes （v2, v4 and vl） show entirely positive pressure dependence. The slopes dω/dP of the internal modes exhibit two sudden changes at O. 73 GPa and 7.13 GPa, respectively. A new lower frequency mode （225 em-1） appears at 3.03 GPa, and the splitting of v2, v3 and v4 occurs at about 7.13 GPa. Moreover, Raman spectra of Fermi resonance show that the relative position of the v1 ＋ v4 combination and the v3 fundamental firstly interchanges corresponding to that at ambient pressure, then the v1 ＋ v4 combination disappears in the gradual process of compression. It is indicated that the pressure-induced phase transition from CC14 Ⅱ to CC14 Ⅲ occurs at 0.73 GPa, and CC14 Ⅲ undergoes a transition to CC14 IV below 3.03 GPa. Further CC14 Ⅳ transforms in a new high-pressure phase at about 7.13 GPa, and the symmetry of the new high-pressure phase is lower than that of CC14 Ⅳ. All the transitions are reversible during decompression.
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