Nos travaux concernent la synthèse et la caractérisation d'oxydes dopés par la méthode d'électrodéposition sous champ magnétique.L'enjeu d'une telle recherche est double puisqu'il associe une étude de synthèses électrochimiques et l'obtention de matériaux associant des propriétés semi-conductrices et magnétiques.Les oxydes étudiés sont l'oxyde de cuivre (I) dopé par le manganèse ou par le cobalt, et l'oxyde de zinc dopé par le cuivre.Notre objectif est l'élaboration sous champ magnétique d'oxydes de type DMS (semi-conducteurs magnétiques dilués), et leurs caractérisations physiques et chimiques.En effet, l'addition du dopage et celui du champ magnétique appliqué pendant l'électrodéposition génèrent des effets sur les matériaux électrodéposés.Nous avons ainsi mis en évidence des modifications au niveau de la morphologie, de la texture, de la composition, et des propriétés optiques ou magnétiques des matériaux obtenus. / Our work focuses on the synthesis and characterization of doped oxides by electrodeposition method under magnetic field superimposition.The goal of this research presents two challenges, because it combines a study of electrochemical synthesis and obtaining materials with optical and magnetic properties. The materials which have been studied are manganese or cobalt doped copper (I) oxide on the one hand, and the copper doped zinc oxide in the other hand.Our goal is the elaboration of diluted magnetic oxides, and the study of their physical and chemical characterizations.Indeed, the effects of doping and of the magnetic field applied during the electrodeposition can provide interesting changes in morphology, texture, composition and optical and magnetic properties of the obtained materials.

In this work the Point Charge Electrostatic Model (PCEM), the Simple Overlap Model (SOM) and the Method of Equivalents Nearest Neighbors (MENN) were applied to a well known series of oxides, namely, Gd2O3, Y2O3, Lu2O3, In2O3 and Sc2O3, all doped ion Eu3+ with the purpose of discussing the charge of interaction and some aspects of the crystal field effect. To this end, calculations were made of the crystal field and crystal field strength parameters and splitting of the 7F1 level of the luminescent ion. By using the luminescent site local structure, the PCEM, as expected, led to satisfactory results only from the qualitative point of view. With the SOM and the MENN it was possible to reproduce the experimental splitting of the 7F1 energy level and its sublevels, with physically acceptable charge factors. Only in some cases the NN charge has been greater than its valence. A discussion on the position of the charge of interaction also has been made. / Neste trabalho o Modelo Eletrostático de Cargas Pontuais, o Modelo de Recobrimento Simples e o Método dos Vizinhos Equivalentes foram aplicados a uma série bem conhecida de óxidos, a saber, Gd2O3, Y2O3, Lu2O3, In2O3 e Sc2O3, todos dopados com o íon Eu3+, com o objetivo de discutir a carga de interação e aspectos do efeito do campo cristalino. Para isso, foram feitos cálculos de parâmetros do campo cristalino, de parâmetro de força do campo cristalino, dos subníveis e desdobramento do nível 7F1 do íon luminescente. Usando a estrutura local do sitio luminescente, o modelo eletrostático, como esperado, levou a resultados satisfatórios apenas do ponto de vista qualitativo. Já com o modelo de recobrimento simples e com o método dos vizinhos equivalentes foi possível reproduzir o desdobramento experimental do nível de energia 7F1 e os seus subníveis, com fatores de carga fisicamente plausíveis. Em apenas alguns poucos casos a carga dos primeiros vizinhos foi maior que a valência respectiva. Também está feita uma discussão sobre a possível posição desta carga de interação.