Pressure-induced phase transitions in organic molecular crystals: a combination of X-ray single-crystal and powder diffraction, Raman and IR-spectroscopy

摘要

The contribution summarizes the results of recent studies of phase transitions induced by high pressure in a number of molecular organic crystals, such as polymorphs of paracetamol, chlorpropamide, polymorphs of glycine, L- and DL-serine, beta-alanine. The main attention is paid to the following topics: (1) Reversible/irreversible transformations; (2) Different behavior of single crystals/powders; (3) The role of pressure-transmitting liquid; (4) The role of the kinetic factors: phase transitions on decompression, or after a long storage at a selected pressure; (5) Isosymmetric phase transitions; (6) The role of the changes in the hydrogen bond networks/intramolecular conformational changes in the phase transitions; (7) Superstructures/nanostructures formed as a result of pressure-induced phase transitions.