2D isostructural Ln(III)-based coordination polymer derived from Imidazole carboxylic acid: Synthesis, structure and magnetic behavior

Abstract

Three new lanthanide-based two-dimensional network like coordination polymers with formula, {[Ln(L)(H2O)2]·2H2O}n (Ln = Ce (1), Gd (2), Sm (3), H3L = 2-(4-carboxy-phenyl)-1H-imidazole-4,5-dicarboxylic acid) have been synthesized hydrothermally and characterized by microanalyses, FT-IR and in case of 1 using single crystal X-ray diffraction. Further, powder X-ray diffraction (PXRD) and thermogravimetric analyses (TGA) have been performed to assess the phase purity and thermal stabilities of all three polymers. Structural analysis showed that adjacent Ce(III) ions in 1 are intra-connected to form infinite metal-carboxylate oxygen 1D alternating chain-shaped building blocks. The nature of intermolecular interactions in 1 have been analyzed using Hirshfeld surface analysis. In addition, the magnetic properties of all three polymers indicate large magnetic anisotropy for 1 and 3, and ferromagnetic interaction for 2.