Three isotypic rare earth complexes,catena-poly[[aquabis(but-2-enoato-κ2O,O′)yttrium(III)]-bis(μ-but-2-enoato)-κ3O,O′:O;κ3O:O,O′-[aquabis(but-2-enoato-κ2O,O′)yttrium(III)]-μ-4,4′-(ethane-1,2-diyl)dipyridine-κ2N:N′], [Y2(C4H5O2)6(C12H12N2)(H2O)2], the gadolinium(III) analogue, [Gd2(C4H5O2)6(C12H12N2)(H2O)2], and the gadolinium(III) analogue with a 4,4′-(ethene-1,2-diyl)dipyridine bridging ligand, [Gd2(C4H5O2)6(C12H10N2)(H2O)2], are one-dimensional coordination polymers made up of centrosymmetric dinuclear [M(but-2-enoato)3(H2O)]2units (M= rare earth), further bridged by centrosymmetric 4,4′-(ethane-1,2-diyl)dipyridine or 4,4′-(ethene-1,2-diyl)dipyridine spacers into sets of chains parallel to the [20\overline{1}] direction. There are intra-chain and inter-chain hydrogen bonds in the structures, the former providing cohesion of the linear arrays and the latter promoting the formation of broad planes parallel to (010).
