Two novel lanthanide (Nd, Gd) coordination polymers with chromate anion as building block of the 2D metal oxide

Two novel lanthanide coordination polymers, [Nd(IN)CrO4]n (1) and [Gd(IN)CrO4]n (2) (HIN = isonicotinic acid), were obtained from the reaction of Ln2O3, HIN and K2Cr2O7 under hydrothermal conditions. The single-crystal X-ray diffraction studies reveal that 1 and 2 are isostructural. Compounds 1 and 2 are three-dimensional frameworks consisting of inorganic layers of Ln and image pillared by the organic IN. Each image anion in the structure binds four Nd(III) ions in an η3,μ4-pentadentate coordination mode. Measurements of magnetic susceptibilities for Compounds 1 and 2 indicate the presence of antiferromagnetic interactions.