On the Subset of Intermolecular Contacts Generating a Molecular Crystal: Topological Features of Organic Minerals
A. M. Banaru, D. А. Banaru, Sergey M. Aksenov
Abstract
A topological analysis of the crystal structures of all known molecular organic minerals with deposited structural data (14 crystal structures) has been performed. The critical net of intermolecular contacts, containing bearing contacts, has been revealed in each structure. It is shown that the number of symmetrically independent bearing contacts in the structures of acetamide, dinite, guanine, and urea minerals coincides with the exact lower boundary inf( $${\text{CN}}_{{{\text{crit}}}}^{'}$$ ). In the structures of acetamide, dinite, karpatite, urea, fichtelite, guanine, idrialite, and ravatite, all bearing contacts should be chosen in a single way (i.e., they are strict). All strict generating (often corresponding to H bonds and C–H···π interactions) and strict non-generating (often corresponding to π···π interactions) contacts have been identified, and their energies have been calculated within the additive atomic approximation. The information complexity of the net of intermolecular contacts and that of the minimal subset of generating contacts, interrelated to its degree of fuzziness, are obtained.