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The title molecule, C₂₂H₆F₈, crystallizes in the monoclinic space groupP2₁/cwith two unique molecules in the asymmetric unit andZ= 8. Each molecule features a short intramolecularsp²-C—H...F hydrogen bond with H...F separations at 2.363 (14) and 2.270 (14) Å, corresponding to 91 and 87.5% of the sum of the van der Waals radii, and C—H...F angles of 158.3 (14) and 166.8 (14)°, respectively. Each molecule also forms an intermolecular bifurcated CH...(F)₂interaction with H...F distances ranging from 2.500 (16) to 2.597 (17) Å. 

The structures of a series of 2:1 cocrystals formed between 4-(dimethylamino)pyridine and each of 1,2,4,5-tetrachloro-3,6-diiodobenzene, 2C₇H₁₀N₂·C₆Cl₄I₂, 1,2,4,5-tetrabromo-3,6-diiodobenzene, 2C₇H₁₀N₂·C₆Br₄I₂, 1-bromo-4-iodo-2,3,5,6-tetrafluorobenzene, 2C₇H₁₀N₂·C₆BrF₄I, and 1,2-dibromo-4,5-difluoro-3,6-diiodobenzene, 2C₇H₁₀N₂·C₆Br₂F₂I₂, are reported. In all five structures, the core halogen-bonded 2:1 trimolecular units have geometrically similar parameters, with the central halogen-bond donor flanked by two pyridine halogen-bond acceptors twisted with respect to the central halogen-bond donor at angles ranging from 76 to 86°. The I...N halogen-bond separations are all short, ranging from 73.3 to 76.7% of the sum of the van der Waals radii, while the C—I...N bond angles are essentially linear. The Br...N halogen-bond separation in the cocrystal formed with 1-bromo-4-iodo-2,3,5,6-tetrafluorobenzene is 80.4% of the sum of the van der Waals radii. Subtle differences in the crystal packings are attributed to the role of secondary C—H...π and weak π-type interactions with chloro and bromo substituents. The cocrystals 2C₇H₁₀N₂·C₆Cl₄I₂and 2C₇H₁₀N₂·C₆Br₄I₂are isomorphous. 

The formation of supramolecular parallelograms utilizing iodoalkyne–pyridine halogen bonding is described. 

The formation of a halogen-bonded co-crystal based upon 1,2-bis(2-pyridyl)ethylene along with iodoperchlorobenzene is reported. The co-crystal undergoes a nearly quantitative [2 + 2] cycloaddition reaction in the organic solid state. 

The formation of a series of isostructural three-component co-crystals between 1,2,4,5-tetrachloro-3-iodobenzene and each of three isosteric bipyridines is reported. 

The present study evaluates the potential combination of charge-transfer electron-donor–acceptor π–π complexation and C—H hydrogen bonding to form colored cocrystals. The crystal structures of the red 1:1 cocrystals formed from the isomeric pyridines 4- and 3-{2-[4-(dimethylamino)phenyl]ethynyl}pyridine with 1-[2-(3,5-dinitrophenyl)ethynyl]-2,3,5,6-tetrafluorobenzene, both C 14 H 4 F 4 N 2 O 4 ·C 15 H 14 N 2 , are reported. Intermolecular interaction energy calculations confirm that π-stacking interactions dominate the intermolecular interactions within each crystal structure. The close contacts revealed by Hirshfeld surface calculations are predominantly C—H interactions with N, O, and F atoms. 

Abstract A molecular rotor is created when a 2,1,3‐benzothiadiazole rotator is incorporated into a rigid arylene ethynylene framework supported by pyridine coordination to a metal (Ag⁺or PdCl₂) guest. Comparisons to a similarly sized naphthyl rotator via¹H NMR spectroscopy provide insights into the movement of these bicyclic rotators relative to the rigid stator framework. Chemical shift increases of 0.3 ppm, or more, upon metal complexation are consistent with through‐space interaction of the central arene with a bound PdCl₂guest. Further study via X‐ray crystallography illustrates that rotation of the 2,1,3‐benzothiadiazole unit in the solid state is likely hampered by relatively strong chalcogen bonding (N⋅⋅⋅S distance of 2.93 Å), forming 2S‐2N squares between benzothiadiazoles of neighboring complexes. Strong π–π interactions (3.29–3.36 Å) between neighboring complexes likewise restrict solid‐state rotation of the potential benzothiadiazole rotator. Modest changes to UV–vis spectra upon metal coordination suggest that electronic properties are mostly independent of stator configuration. 

The formation and crystal structure of a zigzag network held together by I...N halogen bonds is reported. In particular, the halogen-bond donor is 1,3-diiodoperchlorobenzene ( C 6 I 2 Cl 4 ) while the acceptor is the photoproduct rtct -tetrakis(pyridin-4-yl)cyclobutane ( TPCB ). Curiously, within the resulting co-crystal ( C 6 I 2 Cl 4 )·( TPCB ), the photoproduct accepts only two halogen bonds between neighbouring 4-pyridyl rings and as a result behaves as a bent two-connected node rather than the expected four-connected centre. In addition, the photoproduct, TPCB , is also found to engage in C—H...N hydrogen bonds, forming an extended zigzag chain.