Rare Earth Type Materials and Its Industrial Applications

Abstract

The master aim of this article is to describe and analyse the properties of the rare earth elements and its associated material with reference to the outstanding properties as demanded by the modern industry. It is worthwhile, to point out that these material exhibit remarkable properties and have led to the development of new technologies which allow the final goal of utilisation of these rare elements. At this point, we have focused our attention upon a calculation model and the many processes that should be taken into account to provide the best possible description for the experimental data available from the literature for this kind of material. The subject is indeed broad and we have decided to concentrate our efforts in some periodical properties from the microscopic viewpoint which are most like to influence our understanding of these materials and to be in the position to put forward additional knowledge in the state of the art. We will focus our effort to analyse those factors upon which both the crystal radii and effective ionic radii for these rareearth ions, depend upon. This is crucial when dealing with the synthesis and observed properties of these materials and as we shall see the inclusion of concepts such as the multi-variable function upon which these ionic radii depend upon may give us a reasonable rout for industrial processes to synthesise these materials, taking into account the type of ligand subsystems, the surrounding, the coordination number, the oxidation states. In this work, we shall inform the ionic radii for the whole series of the rare earth elements for the oxidation states (a) +2 and coordination number 6, (b) +3 and coordination number 6, (c) +3 and coordination number 7, (d) +3 and coordination number 8, (e) +3 and coordination number 9, (f) +3 and coordination number 12. Some additional applications will be developed in the text thoroughly.