Russian Scientists Conduct the First in the World Study of Electron Density in Appel's Salt Crystals

A research study important for the world science has been conducted by scientists of South Ural State University (SUSU) jointly with their colleagues from other research institutes. They have discovered the reasons for the stability of salts and have provided a detailed description of the results in a top-rated journal Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials (Q2).

Research on organic crystals sparks active interest among scientists, as those are widely used in various fields: from organic semiconductors and solar cells components, to medical chemistry. Specialists study different properties of crystals, and among the relevant topics is considering the specifics of the electron density distribution. Thanks to this information, it becomes possible to predict the physical and chemical, photoelectrical, and other properties of materials, which have the molecular compounds under study in their composition.

This work has become one of the fields within the project on "On the way towards new hybrid materials: digital modelling of the structure and properties from the atomic-molecular-level to nanoparticles" being fulfilled by the researchers of South Ural State University jointly with their colleagues from research institutes of the Russian Academy of Sciences.

"We have become the first in the world to study the experimentally obtained electron density distribution in Appel's salt crystals being the precursor in the synthesis of stable radicals," shares project head, Doctor of Sciences (Chemistry) Ekaterina Bartashevich.

Doctor of Sciences (Physics and Mathematics), Professor Vladimir Tsirelson (one of the originators of the scientific field of quantum crystallography) is developing a theory, which would allow to taka a sneak peek of the subatomic level of the structure of multicomponent materials.

For the experiment, Candidate of Sciences (Chemistry) Oleg Bolshakov synthesized quality single crystals, being guided by the experience of the group lead by Doctor of Sciences (Chemistry) Oleg Rakitin from the N.D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, who study the heterocyclic systems based on substituted dithiazoles. The next step was to collect the X-ray diffraction data in the conditions of continuous cooling. This labour-intensive experiment was performed by Mikhail Miniaev from the N.D. Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences, and Adam Stash from the A.N. Nesmeyanov Institute of Organoelement Compounds. To build reliable models and interpret the obtained data, the capacities of the SUSU Supercomputer Centre were used; in particular, the work was performed by Candidate of Sciences (Chemistry) Irina Iushina.

The research yielded an important conclusion: the reason for the stability of free-radical salts should be sought for at the level of the properties of electron density distribution. They are concealed in the specifics of the formation of chemical bonds, which are of multi-centre character.

The scientists will not stop there. They are planning on continuing the research work at the level of modelling and at the level of experimental studies of the structure and electronic properties of organic crystals.

South Ural State University (SUSU) is a university of digital transformations, where innovative research is conducted in most of the priority fields of science and technology development. In accordance with the strategy of scientific and technological development of the Russian Federation, the university is focused on the development of big scientific interdisciplinary projects in the field of digital industry, materials science, and ecology. In the Year of Science and Technology, SUSU has become the winner in the in the competition under the Priority-2030 program. The university acts as a regional project office of the World-class Ural Interregional Research and Education Centre (UIREC).

More information:
onlinelibrary.wiley.com/iucr/d … 07/S2052520621005928

Provided by South Ural State University