AZOLES .29. STRUCTURE OF THE MOLECULAR-COMPLEX OF 3,5-DINITROINDAZOLE WITH PIPERAZINE AND WATER (2/1/2)

C4H12N2(2+).2C7H3N4O4-.2H2O, M(r) = 538.43, monoclinic, P2(1)/c, a = 12.818 (3), b = 13.769 (4), c = 6.701 (1) angstrom, beta = 104.60 (2)-degrees, V = 1144.5 (5) angstrom-3, Z = 2, D(m) = 1.56 (1), D(x) = 1.56 Mg m-3, lambda-(Cu K-alpha) = 1.54178 angstrom, mu-(Cu K-alpha) = 1.005 mm-1, F(000) = 560, room temperature, final R = 0.035 for 1209 observed reflections. The piperazine ring lies on the centre of symmetry. Piperazine forms a double H2N+< ammonium cation as a result of the incorporation of two protons from the pyrrole N(1) and N(1i) [(i) 1 - x, 1 - y, 1 - z] nitrogen atoms. The indazole system is slightly folded, the maximum deviation [atom C(9)] from the least-squares plane being 0.034 (3) angstrom. The piperazinium cation has a chair conformation and forms a dihedral angle of 85.1 (1)-degrees with the indazole system. The crystal lattice contains an infinite three-dimensional network of hydrogen bonds, in which the water molecules exhibit both donor and acceptor functions.