Syntheses, crystal structures and properties of two 1-D organic-inorganic hybrid phosphotungstates based on Dawson subunits and lanthanide complexes

摘要

Two 1-D organic-inorganic hybrid phosphotungstates based on Dawson subunits and lanthanide complexes [Ln(DME)(6)(H2O)][Ln(DME)(4)(H2O)(4)][alpha-P2W18O62]center dot 2H(2)O (Ln(3+) = Ce3+ for 1, Nd3+ for 2) (DMF = dimethylformamide) were synthesized in aqueous solution and further characterized by elemental analyses, IR spectra, thermogravimetric analyses and single-crystal X-ray diffraction. It is the most prominent feature of 1 and 2 that adjacent [alpha-P2W18O62](6-) polyoxoanions are linked by [Ln(DMF)(6)(H2O)](3+) cations to form a 1-D infinitely zigzag chain and the 1-D chains are aligned in an -ABAB- fashion in the be plane. In addition, the [Ln(DMF)(4)(H2O)(4)](3+) cation only grafts to the "cap" site of the [alpha-P2W18O62](6-) polyoxoanion by a terminal oxygen atom. Besides, the solid-state fluorescence properties and lifetime decay behavior of 2 in the near infrared region have also been investigated in detail. (C) 2018 Elsevier B.V. All rights reserved.