Multi-Nuclear Rare-Earth-Implanted Tartaric Acid-Functionalized Selenotungstates and Their Fluorescent and Magnetic Properties.

A family of multinuclear rare-earth (RE)-implanted H2tart2--functionalized selenotungstates (STs) [H2N(CH3)2]13H{[W2O5(OH)2(H2tart)2](H2tart){[W3O6RE2(H2O)6][SeW9O33]2}2}·31H2O [RE = Eu3+ (1), Tb3+ (2), Dy3+ (3), Ho3+ (4), Y3+ (5); H4tart = d-tartaric acid] have been afforded by a simple one-pot aqueous reaction and were structurally characterized. Intriguingly, their isomorphous organic-inorganic hybrid anion {[W2O5(OH)2(H2tart)2](H2tart){[W3O6RE2(H2O)6][SeW9O33]2}2}14- includes two sandwich-type {[W3O6[RE2(H2O)6][SeW9O33]2}4- dimeric units with a W-O-RE heterometal core, which are further joined by two H2tart2--decorated dinuclear tungsten-oxo {W2O5(OH)2(H2tart)2} clusters and a bridging H2tart2- ligand, contributing to a surprising Mobius band-like configuration. It is worth emphasizing that three H2tart2- ligands coordinate with tungsten centers rather than RE cations. For all we know, 1-5 delegate the infrequent RE-implanted STs functionalized by triplicate H2tart2- bridges. Furthermore, fluorescent performances of 1-4 as well as magnetic properties of 2-4 have been surveyed. The solid-state fluorescence emission spectra prove that each of them undoubtedly shows the characteristic emission peaks of RE cores, while alternating-current susceptibility measurements suggest field-induced single-molecule magnetic behavior in 3.