Topological representations of crystal structures: generation, analysis and implementation in the TopCryst system
Main modern approaches to the topological representation of crystal structures of different chemical classes are overviewed. The problem of automated generation and analysis of such representations is discussed, and a new free web service is presented, which enables the user to describe topological features of crystal structures of any complexity and chemical composition in a fully automated mode. The service requires only an input file with crystallographic information in the standard CIF format and generates all reasonable representations of the structure by selecting structural units with rigorous algorithms. Then the representations are assigned to known topological types and relations to other crystal structures, which have to same architectures, are established. The service is interfaced to a set of topological databases, which in turn have gateways to world-wide crystallographic databases. A number of examples of topological analysis of different classes of chemical structures are presented, and an outlook is given for further development and applications of the service for big data analysis and data mining in crystal chemistry and materials science.