Structure, electronic spectrum and angular-overlap bonding parameters of Bis[bis(pyrazol-1-yl)(2-thienyl)-methane](nitrato-O,O')nickel(II) Nitrate

The crystal structure of the complex [Ni(pz(2)thCH)(2)(O(O')NO '')]NO3 has been determined by X-ray diffraction, where pz and th represent the pyrazolyl and thienyl groups of a potentially tripodal ligand. The thienyl groups are not bound to the metal, which is coordinated to four pyrazolyl groups and a chelating nitrate ion. The electronic 'd-d' transition energies are interpreted in terms of angular-overlap bonding parameters which agree well with those reported for other similar complexes.