Abstract
Two new hybrid Dawson-based polyoxotungstates, [Mn(2,2′-bipy)3]H2[Mn(2,2′-bipy)2][P2W18O62] (1) and [Co(H2biim)3)]2H2[P2W18O62] · 8H2O (2) (2,2′-bipy = 2,2′-bipyridine, H2biim = 2,2′-biimdazole), have been prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectra, thermogravimetric analyses (TGA), X-ray photoelectron spectroscopy (XPS), and photoluminescence spectra. Compound 1 is a 1-D zigzag chain constructed from alternate Dawson-type heteropolyanions [α-P2W18O62]6− and metal coordination cations [Mn(2,2′-bipy)2]2+, in which the 1-D chains are extended into a 3-D framework through C–H ··· π and π–π stacking interactions. Compound 2 is a discrete structure consisting of [α-P2W18O62]6− and two [Co(H2biim)3)]2+ cations, forming a 3-D supramolecular framework via N–H ··· O hydrogen bonds and C–H ··· π interactions. Photoluminescence properties of 1 and 2 have been investigated at room temperature.
Acknowledgments
We thank the National Natural Science Foundation of China, the Natural Science Foundation of Henan Province and Foundation of Education Department of Henan Province for financial support.