Refinement of the crystal and molecular structure of tetra-aquabis[dicyanomercury(II)]zinc(II) nitrate trihydrate by neutron diffraction

Abstract

A neutron diffraction study of the title compound has been carried out. Crystals are monoclinic, space group C2/c, with Z= 4 in a cell of dimensions a= 17.587(2), b= 6.659(7), c= 16.144(5)Å, β= 94.84°. Full-matrix least-squares refinement led to R 0.051. The neutron diffraction results agree well with those from an earlier X-ray diffraction study, but in addition show the bonding of the cyanide nitrogen atoms to the zinc, enabling precise location of all hydrogen atoms. Of the seven possible hydrogen bonded interactions suggested previously, six are confirmed. The structure consists of the zinc atom octahedrally co-ordinated by four water molecules an two nearly linear Hg(CN)₂ groups.