Scientists at the NSU Natural Sciences Department Laboratory of Physico-Chemical Fundamentals of Pharmaceutical Materials and the Institute of Solid State Chemistry and Mechanochemistry SB RAS compiled a single review of existing computational methods for studying high pressure phase transitions of organic substances. This work included third-party studies as well as the experience of Novosibirsk scientists. The Novosibirsk scientist’s research was supported by a Russian Science Foundation grant (No. 18-73-00154) on “Development and testing a method for predicting polymorphic transformations in crystals of organic compounds under high pressures”. The results of this research was published in a special issue of the highly rated journal “Crystals”.
Denis Rychkov, Head of the NSU Laboratory, explained their work,
Most of the work devoted to high-pressure polymorphism is carried out only by experimental methods and researchers simply record the presence or absence of a phase transition. These studies leave a very large variation to explain the reasons for a particular systems behavior. In other words, if you know the answer you can always come up with a solution to the problem, but it will not necessarily be correct. Often, according to an experiments results, there is no clear interpretation for the high-pressure transformation. The scheme we have proposed is based on computational methods that allows us to say unambiguously how the phase transition occurs by relying on the energy data at various phases.
The unique work by the Novosibirsk researchers includes the main computational concepts, demonstrating their advantages and disadvantages, and the NSU and ISSCM scientists’ proposal for an optimal scheme using computational methods to study changes in a crystal structure under high pressure. In addition, the review briefly discusses challenges and possible ways to develop phase transition studies of organic compounds under high pressure.