An unusual P3 1 2 framework for the Ni(4,4'-bipyridine)(H2O)4 chain.

catena-Poly[[[tetraaquanickel(II)]-mu-4,4'-bipyridine-kappa(2)N:N'] thiosulfate dihydrate], {[Ni(C(10)H(8)N(2))(H(2)O)(4)]S(2)O(3).2H(2)O}(n), (I), and catena-poly[[[tetraaquanickel(II)]-mu-4,4'-bipyridine-kappa(2)N:N'] sulfate methanol solvate monohydrate], {[Ni(C(10)H(8)N(2))(H(2)O)(4)]SO(4).CH(4)O.H(2)O}(n), (II), are built up of {[Ni(4,4'-bipy)(H(2)O)(4)](2+)}(n) chains (4,4'-bipy is 4,4'-bipyridine) interwoven in an unusual P3(1) fashion. Voids are filled by the corresponding counter-anions and solvate molecules, defining a complex three-dimensional network surrounding them. In both structures, the cationic chains evolve around a set of twofold axes passing through the Ni(II) ions and bisecting the aromatic amines through their N (and their opposite C) atoms.