The large, lanthanide-containing polyoxometalate–carboxylate hybrid K14Li4H20[As6W58O206Ce4(pydc)2(H2O)6]·44H2O (1) (H2pydc = pyridine-2,3-dicarboxylic acid) was synthesized from the versatile precursor [As2W19O67(H2O)]14− through combined disassembly and reassembly processes. The novel macroanion in 1 constitutes two identical subunits with the formula [As3W29O103Ce2(pydc)(H2O)3]19−.
