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organic compounds
The crystal structure of the title compound, C7H5F5NO+·Cl−, consists of two-dimensional networks of hydrogen-bonded primary NH3+ cations and chloride anions with the pentafluorobenzyl moieties located on one side of the layer. To maximize the Coulombic interactions, the Cl− anions approach the NH3+ groups of the neighbouring network along the O—N bond direction [O—N
Cl = 174.3 (2)°]. The NCl distance between the ions belonging to two adjacent networks is 3.066 (2) Å and is shorter than the NCl distances in the N+—HCl− hydrogen bonds [3.099 (3)–3.133 (3) Å].
Cl = 174.3 (2)°]. The NCl distance between the ions belonging to two adjacent networks is 3.066 (2) Å and is shorter than the NCl distances in the N+—HCl− hydrogen bonds [3.099 (3)–3.133 (3) Å]. organic compounds
A new polymorph of 1H-benzotriazole, C6H5N3, with a melting point of 372 K and a crystal density of 1.33 Mg m−3, has been obtained by recrystallization from acetone. The triclinic unit cell contains ten molecules joined by N—HN hydrogen bonds into a discrete large supramolecular macrocycle.
N hydrogen bonds into a discrete large supramolecular macrocycle.organic compounds
A second orthorhombic polymorph (β) of 1H-benzimidazole, C7H6N2, metastable at room temperature, has been obtained. It has a melting point of 431 K and a crystal density of 1.27 Mg m−3. At room temperature, the crystals transform into the well known orthorhombic α form, with a melting point of 445 K. In both polymorphs, benzimidazole molecules are connected into polymeric chains via N—HN hydrogen bonds. However, the mode of aromatic ring interactions differs significantly in the two crystalline forms. In the α form, the molecules show edge-to-face interactions, whereas in the new β form, a sandwich–herringbone arrangement of the aromatic molecules is observed.
N hydrogen bonds. However, the mode of aromatic ring interactions differs significantly in the two crystalline forms. In the α form, the molecules show edge-to-face interactions, whereas in the new β form, a sandwich–herringbone arrangement of the aromatic molecules is observed.organic compounds
1H-Benzimidazole-2-carboxylic acid crystallizes as the monohydrate, C8H6N2O2·H2O, and the organic molecule exists in a zwitterionic form, viz. 1H-benzimidazolium-2-carboxylate. Hydrogen bonds connect the molecules of acid and water into a two-dimensional network.
