Investigation of unusual oxidation state and spin state transition in rare earth transition metal oxides

Abstract

Transition metal oxides construct one of the most interesting classes of inorganic solid materials via manifestation of wide range of structures, properties and their interesting applications. The intriguing properties that stay at the heart of this class of materials are basically the result of altercation of outer d electrons resulting in different type of bond formation. The lanthanides on the other hand are characterized by gradual filling of 4f subshell. The combination of these two classes has produced lots of tertiary and quaternary compounds which are very much fascinating in terM.S. of crystal structure, band structure, different physical and chemical properties etc. As a result, in terM.S. of applicability, these materials have found place at the different industries in the form of catalysts converting harmful chemicals to natural precursors or generating energy from regular common materials, at electrical industries in form of conducting or dielectric materials, as electrode materials of many day to day electrochemical devices. The structural aspect of these oxides is very much diverse. Crystals with complicated structure like well celebrated perovskites, hexagonal ferrites, pyrochlores, spinels, lamellar etc. have been seen. In terM.S. of electrical properties, on one hand numerous electrically insulating oxides can be found and on the other hand metallic oxides have established their concrete place.