Discussion of Nickel Oxide Approaches in LSDA and GGA

Abstract

Methods based on the theory of Density Functional Theory of (DFT) are designed to investigate various properties of microscopic solids. Today, they are capable of dealing with crystal defects, surfaces, interfaces, biological molecules, beyond that, as investigate semicondutividade phenomena, magnetism, superconductivity, hiperfinas interactions, transitions optical, electronic correlations among others. These methods require some approaches to be used in practical calculations, the simplest of these is the approach of the local density of spin (LSDA), which is based on the assumption that electronic systems can be locally represented by a gas of uniform electrons.  An extension of local density approximation of the gradient is widespread (GGA) which, in modeling of effective electronic interactions, takes into account not homogeneous systems. This work discuss the implementation of approaches LSDA and GGA in systems with strong correlations the coulomb, more specifically the nickel oxide (NiO), being conducted by the analysis of the electron density of state in both approaches.