metal-organic compounds
The crystal structures of cis-diamminebis(pyrazole)platinum(II) dinitrate, cis-[Pt(NH3)2(C3H4N2)2](NO3)2, (1), and cis-diamminebis(pyrazole)platinum(II) dinitrate pyrazole solvate, cis-[Pt(NH3)2(C3H4N2)2](NO3)2·C3H4N2, (2), have been determined by X-ray diffraction. Interestingly, compound (1) crystallizes in the centrosymmetric space group P21/n, while compound (2) somehow crystallizes in the noncentrosymmetric space group P21. In both (1) and (2), the two coordinated pyrazole planes are twisted with respect to the Pt coordination planes at angles of between 46.0 (9) and 60.5 (4)°. The free pyrazole molecule contained as a crystal solvent in compound (2) forms a strong hydrogen bond [2.82 (1) Å] with one of the two coordinated pyrazole ligands. In each crystal, the packing is electrostatically stabilized through hydrogen bonds formed between the nitrate O atoms and the amine and pyrazole ligands.