Superstructural diversity in salt-cocrystals: higher-order hydrogen-bonded assemblies formed using U-shaped dications and with assistance of π−–π stacking

Abstract

Salt cocrystals with components that assemble by hydrogen bonds and aromatic anion–molecule stacks (π⁻–π stacks) are reported. U-shaped bipyridines and an isocoumarin carboxylic acid self-assemble to form 5-, 6-, and 10-component aggregates with components in double and quadruple face-to-face stacks. DFT calculations support the π⁻–π stacks to help stabilize the salt cocrystals.