Tuning the topology structures of polymolybdate-based hybrids from interpenetrated framework to interdigitated architecture via changing polymolybdate clusters

Abstract

By introducing different polyoxomolybdates into a Cu–bimb system (bimb = 1,4-bis(imidazol-1-yl) benzene), three new polyoxomolybdate-based inorganic–organic hybrids with distinct architectures, [Cu^II(bimb)_1.5(H₂O)(β-Mo₈O₂₆)_0.5] (1), (Hbimb)₂[Cu^I(bimb)(PMo₁₂O₄₀)]·4H₂O (2) and [Cu^I₄(bimb)₄(SiMo₁₂O₄₀)]·2H₂O (3), have been synthesized under identical hydrothermal conditions and characterized by routine methods. Compound 1 displays an interesting 2-fold interpenetrated structure consisting of two identical layers. When the polyoxomolybdate clusters were changed from β-[Mo₈O₂₆]⁴⁻ to [PMo₁₂O₄₀]³⁻, and [SiMo₁₂O₄₀]⁴⁻, compounds 2 and 3, respectively, were obtained. Compound 2 shows a highly opened three-dimensional framework, while compound 3 exhibits a three-dimensional interdigitated architecture. The different structural features of compounds 1–3 suggest that the influences of different polyoxometalate clusters on structure must play a key role in the process of assembling. Additionally, both the luminescent and electrochemical properties for 1–3 have been investigated.