Self-assembly mechanism based on charge density topological interaction energies

Abstract

The packing interactions have been evaluated in the context of the self-assembly mechanism of crystal growth and also for its impacts on the aromaticity of the trimesate anion. The structure of ethylammonium trimesate hydrate (1) measured at 100 K and a charge density model, derived in part from theoretical structures, is reported. Theoretical structure factors were obtained from the geometry-optimized periodic wave function. The trimesic acid portion of 1 is fully deprotonated and participates in a variety hydrogen bonding motifs. Topological analysis of the charge density model reveals the most significant packing interactions and is then compared to a complementary analysis performed by the Hirshfeld surface method. The results presented herein demonstrate that in organic salt crystals the small structural motifs are most stable and once formed as stand-alone structures, may direct the self-assembly process. Moreover, when intermolecular interactions supported by the electrostatic forces are analyzed, the care must be taken with interpretation of the results of Hirshfeld surface analysis for organic salts crystals.

Hydrogen-Bonding Motifs in Adducts of Allylamine with the 10 Simplest n-Alcohols: Single-Crystal X-ray Diffraction Studies and Computational Analysis

“…The formation of a cocrystal has to be an energetically favored process, of course. Hence, the use of various theoretical methods can be helpful, especially in the analysis of hydrogen-bonding motifs and synthon energies in the crystalline phases based on various approaches. − However, the thermal stability of a resulting multicomponent phase does not necessarily need to be greater than the pure components. Indeed, a recent analysis of pharmaceutical cocrystals based on literature searching showed that more than 85% of such cocrystal systems have melting points between or lower than their corresponding pure mere components …”