Supramolecular coexistence of Co(II) and Ag(I) complexes based on polyoxotungstate and imidazoles: synthesis, crystal structure, and spectroscopic study

2014-04-30T11:35:55Z (GMT) by Wei Wang Yunfeng Qiu Lin Xu

In this work, [Ag(imi)2]5[PW11O39Co(imi)]·2.5H2O (1, imi = imidazole) based on both polyoxometalate and imidazole has been synthesized by using the hydrothermal method. Its structure and spectroscopic properties were determined by single-crystal X-ray diffraction, elemental analysis, IR spectrum, diffuse reflectance UV–Vis spectrum, and thermogravimetric analysis. Single-crystal X-ray diffraction analysis indicates that 1 is a 3-D supramolecular interpenetrating structure, constructed from [Co(imi)]2+ monosubstituted Keggin-type heteropolytungstate and {[Ag(imi)2]+}5 complexes. Imidazole ligands play dual roles in 1, both coordination linker and supermolecule linker. The luminescence spectrum of 1 displays a strong emission peak at 469 nm excited at 208 nm. Coexistence of Co(II) and Ag(I) complexes with 3-D supramolecular architecture may find application in photoluminescent materials and catalysis.