Neodymium coordination polymers with propionate, succinate and mixed succinate-oxalate ligands : synthesis, structures and spectroscopic characterization

Three neodymium (Nd) coordination polymers with propionate, succinate and mixed succinate-oxalate ligands have been synthesized and structurally characterized. Nd2(C3H5O2)6(H2O)3·3H2O (1) has a 1D polymeric structure built with both ninefold and ten-fold coordinated neodymium polyhedra linked through μ2-bridging propionate ligands. Nd2(C4H4O4)3(H2O)2 (2) has a 3D polymeric structure constructed with two distinct ninefold coordinated neodymium polyhedra linked through three types of succinate ligands, two in μ4- and one in μ3-coordination modes. Nd2(C4H4O4)2(C2O4)(H2O)4·3H2O (3) is built with two types of ten-fold coordinated neodymium polyhedra linked through μ4-succinate ligands into 2D undulating layers which are further connected through μ2-oxalate ligands forming a 3D network with channels. Their vibrational modes and thermal stabilities have been further investigated.