Crystal and molecular structure of catena-μ-acetatomonobromodiamminecopper(II), C₂H₉BrCuN₂O₂

Abstract

The crystal structure of catena-μ-acetatomonobromodiamminecopper([I]), C₂H₉BrCuN₂O₂, has been determined by three-dimensional Patterson and Fourier methods, and refined by least-squares procedures to R=4·7%. The orthorhombicPnma unit cell of dimensions a=9·01(1), b=7·60(1), c=10·38(1) Å contains 4 formula-entities. Two oxygen atoms from different acetate groups (Cu-O=2·001(6) and 1·995(5) Å) and two ammonia molecules (Cu-N=1·984(6) Å) coordinate to the copper atom in atrans square-planar arrangement. This is extended to square-pyramidal by a long contact with the bromine atom (Cu-Br=2·865(3) Å). One more long contact with the other oxygen atom of the carboxyl group (Cu-O(1ⁱ)=2·942(7) Å) realizes a distorted octahedral coordination. The acetate groups lie in mirror planes, and bridge the coordination polyhedra in zig-zag chains parallel to [100].