Stacks of acids: Pentafluorobenzoic acid forms heterodimers with benzoic acid and 2,4,6‐trimethylbenzoic acid that assemble into π stacks with alternating phenyl and pentafluorophenyl residues (see picture). Cocrystals of these acids with 1,4‐bisarylbutadiynes contain acid homodimers sandwiched between the diacetylene molecules.

Examination of the solid state structures of 2,1,3benzoselenadiazole complexes with hydrogen or halogen bond donors has demonstrated that the 2,1,3-benzoselenadiazole molecules preferably form centrosymmetric dimers with use of [Se−N] 2 supramolecular synthon, whereas the two remaining nitrogen atoms not involved in the [Se−N] 2 supramolecular interactions can act as acceptors of hydrogen or halogen bonds. Cocrystallization of selenadiazoles with monofunctional hydrogen or halogen bond donors like pentafluorophenol, pentafluorobenzoic acid, or pentafluoroiodobenzene results in formation of binary discrete complexes. One-or two-dimensional aggregates based on selenadiazole [Se−N] 2 dimers as building blocks were prepared using bifunctional hydrogen or halogen bond donors like resorcinol, tetrafluororesorcinol, tetrafluorohydroquinone, and 1,4-diiodotetrafluorobenzene. During the complexation of selenadiazoles with hydroquinone, anilic acid, or chloranilic acid a competition between Se•••N and Se•••O interactions resulted in breaking of the [Se−N] 2 synthon.

Electron deficient iodopentafluorobenzene forms heterodimers with electron rich pyridine donors stabilized by halogen bonding, that are further assembled into polar brick-wall type 2-D network via p-p stacking interactions between aryl and perfluoroaryl moieties.

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N-nitrosamines, whose chirality is solely due to hindered rotation about the N-N bond, are enantioselectively enclathrated by the crystal host matrices of cholic or deoxycholic acid, as evidenced by X-ray crystallography (see structure in picture) and CD spectra.