Syntheses, structures, and optical properties of two cadmium complexes with chelidamic acid

[Cd2(C7H3NO5)2 center dot 4(H2O)]n center dot 3nH2O center dot 0.5n(CH3OH) (1) and [Cd3(C7H2NO5)2 center dot 10(H2O)] center dot 2H2O center dot 0.5CH3OH (2) were synthesized and characterized by X-ray single-crystal diffraction. The crystal structure of 1 reveals that both Cds are seven-coordinate with pentagonal bipyramid geometries. Coordination polyhedra are interlinked into a 1-D chain, further linked by hydrogen bonds into a 3-D network. Complex 2 is a discrete structure, then independent [Cd3(C7H2NO5)2 center dot 10(H2O)] are linked by hydrogen bonds into a 3-D network. The optical properties of 1 and 2 were investigated with fluorescent spectra; both exhibit strong green luminescence probably originating from -* transition of the ligand.