Vol. 2, Issue 6 (2017)
An analysis on electronic and structural transformation in divalent rare earth chalcogendie
Author(s): Dr. Ravindra Kumar
Abstract: The electronic structure of the praseodymiummonopnictides and monochalcogenides is studied using the self-interaction corrected (SIC) local spin density (LSD) approximation. This method allows for a description of the Pr ions with some f electrons localized in atomic like orbitals, while other f degrees of freedom are forming hybridized bands. In addition the electronic structure of rare earth monosulfides were studied by Me Clure using a simple model, which correlates the magnetic susceptibility data with the type of electrical conductivity, observed. Theoretical study of pressure induced phase transitions in cerium Chalcogenides were carried out by Svane using the SIC-LSD approximation. Phase transformation studies on samarium monochalcogenides were carried out experimentally up to 55 GPA which reports a high pressure NaCl type to CsCl type phase transition in SmSe and SmTe. Rare earth monochalcogenides including monoxides crystallize in face centered cubic structure of NaCl type. The Chalcogenides of rare earth metals are one such group, which posses a wide range of electrical magnetic and other physiochemical properties. Some of them show valence fluctuations and few others exhibit insulator - metal transition induced either by doping or by high-pressure.