Spectral and Thermal Studies on Bivalent Transition Metal Complexes of Oxalic Acid with Morpholine

Morpholinium transition metal oxalates of the formula (MorpH)2[MII(ox)2 (H2O)2].2H2O, where M = Co, Ni have been prepared by the reaction of respective metal nitrates with aqueous solution of morpholinium oxalate salts in appropriate mole ratios. These compounds have been characterized by various physico-chemical techniques like elemental analysis, conductance measurements, UV-Vis, IR, TG-DTA, XRD and SEM studies. The elemental analysis confirms the desired composition of the complexes. Conductance measurements show that all the complexes behave as 2:1 electrolytes, augmenting the non-coordination of morpholiniumcation. Thermal studies show the presence of two coordinated water molecules and two lattice water molecules. Based on the above results, geometry of the complexes is assigned as octahedral. The powder X-ray diffraction patterns of these compounds are similar to one another suggesting that they are isomorphous.Scanning electron micrographs are also observed to evaluate the morphology and particle size of the complexes.