Two new ladder-like inorganic chains constructed from Cu-containing sandwich polyoxoanions

Abstract

Two heteropolyoxotungstates, K₄Na₄[Cu₂(H₂O)₈Cu₄(H₂O)₂(B-α-GeW₉O₃₄)₂]14H₂O (1) and K₈[Cu₂(H₂O)₈Cu₄(H₂O)₂(B-α-SiW₉O₃₄)₂]4H₂O (2), have been obtained in aqueous solution and characterized by IR, TG, elemental analysis, magnetism, and single-crystal X-ray analysis. The two compounds are one-dimensional (1-D) inorganic polymers composed of Cu-containing sandwich polyoxoanions, linked by additional Cu²⁺ ions to construct 1-D ladder-like chain structures. To the best of our knowledge, it is the first example of a 1-D ladder-like chain based on sandwich-type anions and Cu²⁺ linkers. Furthermore, the chains in 1 are further connected by K⁺ into an extensive three-dimensional (3-D) framework. The magnetic studies of 1 indicate that antiferromagnetic interactions exist in the central tetra-metal set of the sandwich-type polyoxoanion.

Keywords:

• Heteropolyoxotungstates
• Copper
• Sandwich-type
• Ladder-like structure

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 20701005); the Postdoctoral station Foundation of Ministry of Education (No. 20060200002); the Program for Changjiang Scholars and Innovative Research Team in University.