Diakonenko V. The structure of organic crystals based on the analysis of interaction energies between molecules

The thesis is devoted to the development of a new method for studying of a crystal structure of organic compounds, based on the analysis of the interaction energies between molecules in a crystal. Using series of model crystals it was shown that the proposed procedure is quite universal and can be used to study the crystal structure of organic compounds of various types (contained intermolecular interactions with close geometrical characteristics, without any specific interactions or structures of macromolecules). It has been proposed the new method of visualization of the pairwise interaction energies calculated by quantum-chemical methods using energy-vector diagrams. The use of the proposed method for analyzing of the crystal structures of organic compounds has made it possible to distinguish the different levels of organization of molecular crystals (chains/columns, layers, layers consisting of strongly interacting columns), which creates the prerequisites for classifying all organic crystals into isotropic, columnar, layered or columnar- layered. As a further development of the synthon theory it is possible to propose the classification of synthon within the framework of an individual crystal in accordance with what basic structural motif they form (basic, primary, secondary, auxiliary).