Two new dimeric cadmium(II) and zinc(II) sulfate complexes with 2,4,6-tris(2-pyridyl)-1,3,5-triazine and 2,2:6',2"-terpyridine.

The structures of two new sulfate complexes are reported, namely di-mu-sulfato-kappa(3)O,O':O"-bis(aqua[2,4,6-tris(2-pyridyl)-1,3,5-triazine-kappa(3)N(1),N(2),N(6)]cadmium(II)) tetrahydrate, [Cd(2)(SO(4))(2)(C(16)H(12)N(6))(2)(H(2)O)(2)].4H(2)O, and di-mu-sulfato-kappa(2)O:O'-bis[(2,2':6',2"-terpyridine-kappa(3)N(1),N(1'),N(1"))zinc(II)] dihydrate, [Cd(2)(SO(4))(2)(C(15)H(11)N(3))(2)].2H(2)O, the former being the first report of a Cd(tpt) complex [tpt is 2,4,6-tris(2-pyridyl)-1,3,5-triazine]. Both compounds crystallize in the space group P-1 and form centrosymmetric dimeric structures. In the cadmium complex, the metal center is heptacoordinated in the form of a pentagonal bipyramid, while in the zinc complex, the metal ion is in a fivefold environment, the coordination geometry being intermediate between square pyramidal and trigonal bipyramidal. Packing of the dimers leads to the formation of planar structures strongly linked by hydrogen bonding.