research Essay --

An intense research into the structural, physical and canalise properties of perovskite manganites with the general formula of R1-xAxMnO3 (where R-rare earth element like La, Pr, Nd, Sm, and A - double element like Sr, Ca, Ba, and Pb) has been of recent interest due to colossal magnetoresistance (CMR) discovery1-3.Attempts swallow been made to control the effective of one electron band breadth which primarily governs the magnetic and transport properties of the manganites through doping at the R and A sites4-6. In view of the complexity of the manganites, the knowledge on the relationship amongst the metalinsulator (MI) transition and ferromagnetic (FM)paramagnetic (PM) transition in CMR manganite perovskites is ever increasing due to its potential applications 7-9. The metallic properties of doped manganites such as La1-xSrxMnO3 (LSMO) with large band width are explained employing the double permutation (DE) theory 10-13. It is inferred from the above studies that the narrow band width is not alone responsible for the observed MI transition and CMR in manganites like La1-xCaxM...