Synthesis and magnetic properties of tartrate-bridging rare-earth-containing polytungstoarsenate aggregates from an adaptive precursor [As2W19O67( H2O)](14-)

Six tartrate-bridging rare-earth-substituted polytungstoarsenates [RE2(C4H4O6)(C4H2O6)(As W9O33)](2)(18-)( Ho-III (1), Er-III (2), Tm-III (3), Yb-III (4), Lu-III (5), and Y-III (6)) have been synthesized under conventional solution conditions. They have been further characterized by elemental analyses, X-ray powder diffraction (XRPD), IR and UV-vis spectroscopy and single-crystal X-ray diffraction. Preliminary variable-temperature magnetic susceptibility measurements indicate that 1-4 exhibit antiferromagnetic coupling.