Crystal structure of aquabis(dimethylglyoximato)nitrocobalt(III) based on neutron diffraction data

Single crystal neutron diffraction confirmed previously reported X-ray resu lts: Co(Hdmg)(2)(NO2)(H2O) (Hdmg = dimethylglyoximate) crystallizes in the monoclinic space group P2(1)/m with lattice constants a = 7.605(5) Angstrom : b = 8.907(5) Angstrom, c = 10.721(5) Angstrom, beta = 94.07(3)degrees, V = 724.4(7) Angstrom(3) and Z = 2 with the complex molecule on a mirror plan e. In addition, the neutron diffraction experiment yielded accurate positio ns for all hydrogen atoms: The intramolecular hydrogen bridges O-H ... O ar e asymmetric with distances O-H = 1.044(7) Angstrom and O ... H = 1.468(7) Angstrom, and hence the chelating ligands are not equivalent. This intramol ecular result correlates to the packing arrangement: The acceptor oxygen at om of the intramolecular bridge is also involved in strong intermolecular h ydrogen bonding.