Synthesis, crystal structure, and properties of a new cadmium(ΙΙ) polymer with mixed Cl⁻/SCN⁻ ligands: [CdCl(SCN)]_n

Abstract

A 1-D chain complex, cadmium(ΙΙ) chloride thiocyanate (1), [CdCl(SCN)] _n was synthesized by evaporation and characterized by single-crystal X-ray diffraction and FT-IR techniques. The compound crystallizes in the space group Pnma of orthorhombic system with cell parameter a = 9.5967(7), b = 4.2595(3), and c = 10.1789(7) Å; V = 416.08(5) ų and Z = 4. The cadmium(ΙΙ) is five-coordinate, surrounded by one pair of (µ-1,1-NCS) bridging NCS⁻ and three Cl⁻ as a µ₃-linker coordinating three Cd(ΙΙ) centers, approximately a severely distorted square-pyramidal configuration. Cd(ΙΙ), Cl⁻, and SCN⁻ form an infinite 1-D chain with chair-like features, a new example of mixed Cd–NCS–Cl discrete compounds. The photophysical properties of the crystals have been investigated with one emission peak at 473 nm observed for the title complex in the solid state, which exhibits blue luminescence. The mechanical properties of the crystals have been studied using Vickers microhardness tester and the hardness was 78.6 kg mm⁻².

Keywords:

• Cadmium(ΙΙ) coordination polymer
• Crystal structure
• Photoluminescence properties
• Mechanical properties

Acknowledgments

This work was supported by the Fund for the Doctoral Program of Nanchang Hangkong University (No. EA200601189).