Intermolecular Interactions in the Crystal Structure of Bis(4-methylcyclohexylammonium) tetrabromocuprate(II)

The crystal structure of (4-methylcyclohexylammonium)2[CuBr4], 1, belongs to the monoclinic system, space group P21/n with cell constants a = 8.1687(2) Ǻ, b = 12.1569(3) Ǻ, c = 22.3921(3) Ǻ, β = 94.8290(10)°, Z = 4. The structure was solved by direct methods and refined to R = 0.0685 (wR2 = 0.1287). The structure analysis reveals that the Cu(II) has an intermediate geometry between regular tetrahedral (Td ) and square planar (D4h). In the crystal structure of 1, the cations and anions are arranged in alternating stacks. The stacks are connected via classical hydrogen bonding of cationic NH3+ groups and Br- of CuBr42- into a supramolecular architecture parallel to a axis. The absence of other interactions [(p)C―H…Br, p…p and Br… p] allow segregation of cation and anion stacks into distinct polar and non-polar regions.