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

Abstract

[Cd₂(C₇H₃NO₅)₂ · 4(H₂O)] _n · 3nH₂O · 0.5n(CH₃OH) (1) and [Cd₃(C₇H₂NO₅)₂ · 10(H₂O)] · 2H₂O ·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 · 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 π–π* transition of the ligand.

Keywords:

• Cadmium complexes
• Coordination polymer
• Crystal structure
• Luminescence
• Syntheses

Acknowledgements

We gratefully acknowledge the financial support by the NSF of China (20801026), the NSF of Jiangxi Province (2008GQC0036), the Jiangxi Provincial Department of Education (GJJ09486), and the financial support by the Aviation Science Foundation of China (2008ZF56012).