Polymorphism, Crystal Habit and Intermolecular Contact Topology in Benzothiazine Derivatives: A Comparative Hirshfeld Surface Analysis of Seven Crystal Structures
Year: 2026
Type: preprint
Abstract: Seven deposited benzothiazine crystal structures (CCDC 1835802, 1835803, 1964377–1964379, and 2102851–2102852) were reanalysed to distinguish differences in periodic crystal structures from crystal habit and positional disorder. Eight independent molecular environments were evaluated with fragment-based Hirshfeld surfaces and element-resolved contact contributions in Multiwfn. Convergence was assessed at grid spacings of 0.20 and 0.15 Bohr and with crystal-environment clusters extending to 4 and 6 Å. In the 2018 polymorph pair, H···C/C···H contributions increase from 10.647% in 2M to 16.932% in 2O (6 Å, 0.15 Bohr), whereas H···H decreases from 40.277% to 36.922%. The 2020 deposits share closely similar major contact contributions, with H···F/F···H ranging from 24.193% to 24.600%. The two independent molecules of monoclinic CCDC 2102852 exhibit distinct H···C/C···H fractions of 19.048% and 22.066%. Alternative orientations of the disordered CF 3 group in CCDC 1964379 preserve the identity of the dominant contact categories but change the F···F contribution from 3.482% (major) to 1.884% (minor at all sites) or 2.871% (minor in the central molecule only). This comparative analysis illustrates the need to distinguish polymorphism, habit, disorder and chemical substitution when interpreting contact-area descriptors; percentage contributions do not measure interaction energies.
Source: ChemRxiv
Author: Pavlo Bondarenko
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7223189259