High‐pressure Raman study of liquid and crystalline CHF2Cl and CHF3

Abstract
High‐pressure Raman spectra of liquid and crystalline CHF2Cl and CHF3 were measured up to pressures of 15 and 10 GPa, respectively, at 300 K in a gasketed diamond‐anvil cell. The liquid–solid phase transition pressures were determined to be 3.49 GPa for CHF2Cl and 2.46 GPa for CHF3. For both CHF2Cl and CHF3, the wavenumbers of the CH stretching mode ν1 increased rapidly with increasing pressure, and this behaviour was investigated by the theory of reasonance hybrid of the covalent‐bonded and ionic‐bonded structures.