Synthesis, structure and thermal behaviour of a barium-glutarate framework

A hybrid framework material has been synthesized via a gel diffusive technique. Its X-ray single crystal structure has been determined at 120 K, in the tetragonal space group P42/mbc. The ligand is partially deprotonated giving interesting supramolecular bonding formed by hydrogenoglutarate anion, which can act as a building synthon. The layer-type polymeric structure is built up from isolated polyhedra linked via conventional carboxylate bridges and forming inorganic layers in the plane (001). Along [001], layers consisting of the methylene spacers of the ligands, complete the three-dimensional framework. The thermal analysis performed by TGA and DSC in air and under N2, respectively, revealed the high stability of the non-templated framework (up to 210 °C) and showed several phase transitions and one solid-state reaction detected by an exothermic peak at 500 °C.