Crystal structure of tristrimethylammonium catena-tri-µ-chlorocuprate(1 –) tetrachlorocuprate(2 –)

Abstract

The crystal structure of the title compound has been determined from photographic X-ray data. Crystals are monoclinic, space group Cc, with cell dimensions a= 1430, b= 2467, c= 630 pm, β= 92·52° and Z= 4. The structure was solved by Patterson and Fourier methods and refined by least squares to R 0·101 for 1480 observed reflections. The compound is unusual in having two types of copper-containing anion, a [CuCl₃^–]_n chain and a [CuCl₄]^2– tetrahedron. The symmetry of the crystal lattice is almost hexagonal, and the distortion from hexagonal symmetry is attributed to the Jahn–Teller effect in the [CuCl₃^–]_n chains. The distortion of the tetrahedron differs from that usually found in tetrahedral tetrachlorocuprate(II) complexes in that it approximates to C_3v rather than D_2d symmetry.