Synthesis and Characterizaion of a New Inorganic-organic Sulfate Compound——Crystal Structure of [Ni(H_2O)_6][H_2N(C_2H_4)_2NH_2](SO_4)_2

Ni(H_2O)_6][H_2N(C_2H_4)_2NH_2](SO_4)_2 is an inorganic-organic compound with a new open framework synthesized by hydrothermal method, and characterized by means of single-crystal diffraction and spectroscopic data. The compound crystallized in a monoclinic space group P2_1/n with a=1.29089(2) nm, b=1.06301(3) nm, c=1.33202(4) nm, β=114.0870(10)°, V=1.67127(8) nm 3, Z=4, and was solved by using the direct method and the least-squares refinement converged at R=0.0214[I2σ(I)]. The structure consists of isolated Ni(H_2O)_6 octahedra and SO_4 tetrahedra, with both of them hydrogen-bonded to piperazine cations.