CRYSTAL STRUCTURE OF MU-CHLORO-BIS(CHLOROTETRA(BENZIMIDAZOLE)NICKEL(2)) CHLORIDE-4-ACETONE

The crystal structure of μ-chloro-bis(chlorotetra(benzimidazole)nickel(II)) chloride-4-acetone has been determined by single-crystal X-ray techniques. The crystals are monoclinic, space group P21/c with cell dimensions a = 12.551 (5), b = 16.517 (7), c = 17.794 (7) Å, β = 106.72 (5)°. The unit cell contains two cations of formula Ni2Cl3(C7H6N2)8+, two chloride ions Cl−, and eight molecules of acetone. The observed and calculated densities are 1.35 ± 0.01 and 1.354 g cm−3, respectively. The intensities of 2492 reflections above background were collected by counter methods and the structure has been refined to a conventional R factor of 0.101. The cations are of the form Cl-Ni(C7H6N2)4-Cl-Ni(C7H6N2)4-Cl+, with the bridging chlorine atom on a center of symmetry. The Cl-Ni-Cl-Ni-Cl chain is closely linear (Cl-Ni-Cl = 179.3 (1)°), and the two nickel-chlorine distances are appreciably different (Ni-Cl(terminal) = 2.425 (4) Å, Ni-Cl(bridging) = 2.941 (2) Å). © 1968, American Chemical Society. All rights reserved.