PREPARATION AND CRYSTAL STRUCTURE OF THE HOST-GUEST TYPE COMPLEX OF TRIS(BIPYRIDINE)NICKEL(II)-TETRAKIS(CYANO) NICKELLATE (II))-HEXAHYDRATE-HEMI (BIPYRIDINE)

Abstract

The title complex is built up of [Ni(bpy)₃]²⁺ cations, [Ni(CN)₄]^2? anions and non-coordinated bpy and water molecules. The water molecules along with one of the two crystallographically independent tetracyanonickellate anions form layers, in which H-bonds (HB's) of the types O-H ‥ O and O-H ‥ N are important. The remaining tetracyanonickellate anions bound by H-bonds to water molecules in the layers are placed approximately perpendicular to the layers making interconnection between them. So by HBs a 3D network is formed (hydrophilic host part of the structure). The cations and non-coordinated bpy molecules (hydrophobic guest part of the structure) are placed in cavities formed by HBs. The Ni-N distances in the cation are within the range 2.078(3)-2.100(3) Å and the Ni-C distances in the anion are within the range 1.854(5)-1.873(4) Å.