title: Computing stoichiometric molecular composition from crystal structures.
abstract: Crystallographic investigations deliver high-accuracy information about positions of atoms in crystal unit cells. For chemists, however, the structure of a molecule is most often of interest. The structure must thus be reconstructed from crystallographic files using symmetry information and chemical properties of atoms. Most existing algorithms faithfully reconstruct separate molecules but not the overall stoichiometry of the complex present in a crystal. Here, an algorithm that can reconstruct stoichiometrically correct multimolecular ensembles is described. This algorithm uses only the crystal symmetry information for determining molecule numbers and their stoichiometric ratios. The algorithm can be used by chemists and crystallographers as a standalone implementation for investigating above-molecular ensembles or as a function implemented in graphical crystal analysis software. The greatest envisaged benefit of the algorithm, however, is for the users of large crystallographic and chemical databases, since it will permit database maintainers to generate stoichiometrically correct chemical representations of crystal structures automatically and to match them against chemical databases, enabling multidisciplinary searches across multiple databases.
authors.affiliation: Vilnius University Institute of Biotechnology, Graiciuno 8, LT-02241 Vilnius, Lithuania ; Vilnius University Faculty of Mathematics and Informatics, Naugarduko 24, LT-03225 Vilnius, Lithuania.
authors.forename: Saulius
authors.initials: S
authors.lastname: Gražulis
authors.affiliation: Vilnius University Institute of Biotechnology, Graiciuno 8, LT-02241 Vilnius, Lithuania.
authors.forename: Andrius
authors.initials: A
authors.lastname: Merkys
authors.affiliation: Vilnius University Faculty of Mathematics and Informatics, Naugarduko 24, LT-03225 Vilnius, Lithuania.
authors.forename: Antanas
authors.initials: A
authors.lastname: Vaitkus
authors.affiliation: Vilnius University Institute of Biotechnology, Graiciuno 8, LT-02241 Vilnius, Lithuania.
authors.forename: Mykolas
authors.initials: M
authors.lastname: Okulič-Kazarinas
keywords: molecular structure; multimolecular ensembles