The purpose of this research is to have a quantitative analysis on the temperature dependence magnetization of ferromagnetic nanoparticles (NPs), i.e., the Curie temperature (Tc), was systematically studied. The atomistic simulations were carried out using the VAMPIRE 5.0 software based on the Landau-Lifshitz-Gilbert-Heun method. The variable parameters of the simulations were damping, time step, particle geometry (spherical, cubic, and cylindrical) and particle size. We have calculated λ for Fe and Ni, in addition we have found different Tc values for each nanogeometry studied following a finite-size effect. We have found ν values for cubic NPs close to the reported values. In particular, it was observed that the Tc values for the studied geometries in the case of Fe and Ni decreases from their theoretical bulk values, for a critical particle size diameter less than 5 nm. Hence, the p...

The Rietveld refinement method has taken high relevance since its creation. Nowadays, it is an useful tool in many fields of industry, materials science, and technology. For these reasons, it becomes a need for scientists and engineers whom pretend to use it for proper analysis of their materials. However, the initiation in the method can be slow, taking into account the accelerated rhythm of the research and economic demands. Thus, this work is an intend to fulfill this hole, providing the basic foundations and methodology of the Rietveld refinement in a brief way, this along with the results of its application in superconducting samples of Yttrium Barium Copper Oxide and magnesium diboride, and functional magnetic nanoadsorbents of maghemite and a multiphasic composite (iron oxide, hydroxyapatite and secondary phases). In the process, an in-detail protocol was designed and provided. It...