Poly[bis-(N,N-dimethyl-formamide)tris-(μ4-trans-stilbene-4, 4′-dicarboxyl-ato)-tricadmium(II)]: A two-dimensional network with an unusual 3⁶ topology

In the title compound, [Cd3(C16H10O4)3(C3H7NO)2] n or [Cd3(SDA)3(DMF)2] n (H2SDA is trans-stilbene-4,4′-dicarboxylic acid and DMF is dimethyl-formamide), the linear dicarboxylate ligand forms a two-dimensionally layered metal-organic network with the relatively uncommon 3⁶ topology. The structure reveals trinuclear secondary building units and has an octa-hedral geometry at a central metal ion (occupying a symmetry site) and tetra-hedral geometries at two surrounding symmetrically equivalent metal ions lying on a threefold axis. The six-connected planar trinuclear Cd^II centers, Cd3(O2CR)6, play a role as potential nodes in generation of the relatively uncommon 3⁶ topology. The coordinated DMF unit is disordered around the threefold axis.