catena-Poly­[[(2-hexyl-2H-tetrazole-κN⁴)copper(II)]-di-μ-chloro]

In the title polymeric complex, [CuCl₂(C₇H₁₄N₄)]_n, the Cu coordination polyhedron adopts the form of a distorted square pyramid. Basal sites of the pyramid are occupied by three Cl atoms [Cu—Cl = 2.2519 (7), 2.2842 (7) and 2.3114 (7) Å] and by the N atom of the 2-hexyl-2H-tetrazole ligand [Cu—N = 2.0068 (17) Å]. A Cl atom lies in the apical position, 2.6091 (6) Å from the Cu atom. Neighbouring polyhedra are linked by sharing their edges with Cl atoms to form polymeric chains running along the a axis. The CH₃CH₂– group at the end of the hexyl chain is positionally disordered.

An X-ray powder diffraction study of catena-poly­[[bis(1-methyl-1H-tetrazole-κN⁴)copper(II)]-di-μ-bromo]

The crystal structure of the polymeric title complex, [CuBr₂(C₄H₈N₈)₂]_n, has been solved from X-ray powder data and refined with the Rietveld method using geometrical soft restraints. The Cu atom, lying on an inversion centre, has octahedral coordination, with two N atoms [Cu—N = 2.090 (13) Å] and two Br atoms [Cu—Br = 2.432 (4) Å] in the equatorial positions. The axial sites of the octahedron are occupied by two Br atoms, with Cu—Br distances of 3.101 (4) Å. Each Br atom is a bridge between neighbouring Cu atoms, which is responsible for formation of polymeric layers parallel to the bc plane, with only van der Waals interactions between them.

5-Amino-1-methyl-4H-tetra­zolium picrate

The title compound, C₂H₆N₅⁺·C₆H₂N₃O₇^-, was prepared by the equimolar reaction of 5-amino-1-methyl­tetra­zole with picric acid. In the salt, the N⁴ atom of the tetra­zole ring is protonated. Cations and anions in (I) are linked together by a complex set of hydrogen bonds, forming polymeric chains extending along the a axis, with van der Waals inter­actions between the chains.