High-pressure behavior of hydrogen-bonded organic crystal trifluoroacetamide

This study examines the high-pressure crystal structure of trifluoroacetamide (TFA, C 2 H 2 F 3 NO) up to 15 GPa utilizing in situ high-pressure Raman scattering. Pressure-induced structural changes were tracked using Raman spectroscopy. Significant alterations in Raman spectra between 1.5 and 5.9 GPa indicate a phase transition, which proves to be reversible as the high-pressure phase reverts to the ambient phase upon release of pressure. The observed variations in NH 2 Raman modes in the high-pressure phases suggest that the phase transitions in TFA stem from rearrangements within the hydrogen-bonded networks. Moreover, we have investigated the changes in intermolecular interactions within TFA crystals under pressure using Hirshfeld surface energy and fingerprint plots. This study can provide a reference for the in-depth study of the high-pressure behavior of TFA and other related substances.