Crystal Structure, Thermal Behavior and Magnetic Properties of a Novel Polymer [Ni(dipic)2Mn(O)2]n Synthesized by Reflux and Sonochemistry

Abstract

In this research a new polymer of [Ni(dipic)2Mn(O)2]n where dipic is pyridine-2,6-dicarboxylic acid was synthesized by sonochemical (1) and reflux (2) methods. The crystals of this polymer were prepared by reflux and characterized by single crystal X-ray diffraction)SC-XRD). The crystal structure of this polymer was found to be a binuclear coordination polymer. The structure of single crystal 2 was compared with the structure of this polymer was prepared via sonochemical method, using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), thermal analysis method (TGA), BET specific surface area and vibrating sample magnetometer (VSM). The study of thermal behavior of polymer show, the process of decline weight is the same for these structures but polymer 1 is less stable than of 2, therefore earlier started to decomposition. The magnetic measurements were done at room temperature and show the polymers of 1 and 2 exhibits paramagnetic behavior. A fragment of environmental of [Ni(dipic)2Mn(O)2]n, the MnII ion is tetra-coordination with four μ-carboxylate oxygen from [Ni(dipic)2]2−. The nickel ion in [Ni(dipic)2]2− achieves six-coordination by coordinating with two deprotonated dipicolinate groups which acting as tridentate chelating ligands. The title polymer crystallized in the monoclinic space group Cc.