Ab Initio Approaches to the Electronic Structure of Magnetic Crystals

Abstract

Up to now we have been dealing with some model approaches to the study of magnetic interactions in solids. Along with obvious advantages (clear physical picture of interactions taken into account and, in some cases, an analytical solution), such model approaches have some significant drawbacks. The drawbacks become very prominent when one tries to explain or to predict the properties of real chemical compounds. Here one encounters large uncertainties in model parameters, as well as situations where it is not possible to extract from the calculations a description of any properties which were not included in the model from the very beginning. Complete information on the electronic structure and magnetic interactions in solids can be, in principle, obtained from the solution of the Schrödinger equation for electrons which interact with other electrons and feel the external electric field created by atomic nuclei. For such a system, it is not very difficult to formulate appropriate equations and boundary conditions. What is more important, the proper choice of parameters, which presents a problem in any model approach, does not appear at all. Therefore, one may try to calculate the electronic structure of a solid starting “from first principles.”KeywordsGreen FunctionSpin DensityMagnetic InteractionSpin DirectionLocal Magnetic MomentThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.