Yes / The adsorption of azobenzene (AB), ortho fluoro-azobenzene (FAB) and ortho chlor-azobenzol (ClAB), in both the cis and trans isomers, at the Au(111) and Ag(111) surfaces is investigated using plane-wave density functional calculations with the revPBE-vdW-DF functional. The resulting adsorption energies and internal structures of AB adsorbed to both metal surfaces are in broad agreement with available experimental data. In the gas phase, FAB and ClAB feature a significant reduction in the energy difference between the two isomeric states, compared with AB. This relative reduction in the energy difference is still significant for the adsorbed form of FAB but is only weakly apparent for ClAB. The absorption spectra of the molecules have also been calculated, with the halogen substituents generating significant changes in the gas phase, but only a modest difference for the adsorbed molecules.

L'étude concerne la mise en œuvre du processus de polarisation tout–optique en vue de l'orientation et du contrôle complet de la structuration de matériaux organiques polymères. Il est démontré que la superposition cohérente de deux faisceaux optiques aux fréquences fondamentale et second harmonique permet de briser la centrosymétrie du milieu et d'induire une orientation polaire des molécules photochromiques au sein du matériau. Les paramètres importants qui doivent être contrôlés, permettant une polarisation efficace du matériau, sont la phase relative, les amplitudes et les états de polarisation des faisceaux d'écriture. Nous présentons une technique originale qui est basée sur la dispersion de l'indice de réfraction des verres et qui permet de négliger l'influence de la phase relative sur le processus de polarisation. On montre également que cette nouvelle méthode développée dans le cadre de cette étude permet de réaliser le contrôle en temps réel de l'orientation tout optique. Cette technique est appliquée à plusieurs matériaux polymères possédant des propriétés nonlinéaires intéressantes, et a notamment permis d'observer la formation de réseaux de surface dans des films polymères amorphes contenant des molécules azoïques. La configuration particulière utilisant un prisme permet d'observer une diffusion translationnelle photoinduite des molécules azoïques, cette dernière étant à l'origine de la formation des réseaux de surface. Une analyse des réseaux enregistrées avec des polarisations s (TE) et p (TM) a été effectuée. La formation de ces derniers est attribuée à un transport de matière des régions ou le taux d'isomérisation est élevé vers les régions ou ce taux est plus faible. Nous avons aussi utilisé la technique d'orientation tout–optique afin d'augmenter le rendement de cellules organiques photovoltaïques.

Neste trabalho os complexos cis- [Ru(BAF)(bpy)(PPh3)(OH2)](ClO4)2 (monômero B) e cis-[Ru(dmbpy)2(PPh3)(OH2)](OPh)2 (monômero C) foram sintetizados e caracterizados através de métodos espectroscópicos e eletroquímicos, sendo utilizados na construção de novos eletrodos modificados EMs e aplicados na eletrooxidação de substratos orgânicos. A preparação destes EMs consistiu no recobrimento da superfície de eletrodos de feltro de carbono e de bastões de grafite pelos filmes poliméricos ancorados ao rutênio. Os intervalos de potencial aplicados para a polimerização dos complexos foram àqueles correspondentes, respectivamente, aos potenciais de polimerização do contra-íon difenolato e do ligante azóico contendo o grupamento fenol. A atividade catalítica destes EMs foi investigada através de um estudo cinético, através de eletrooxidações heterogêneas acompanhadas por UV/Vis de diversos compostos orgânicos como: safrol, isosafrol, álcool benzílico, fenil etil álcool, etil benzeno, tolueno, benzaldeído, ciclo hexen-2-ol, demonstrando que os EMs podem ser utilizados como catalisadores em reações de eletrooxidações com rendimentos satisfatórios. / In this work the complexes cis-[Ru(BAF)(bpy)(PPh3)(OH2)](ClO4)2 (B monomer) and cis-[Ru(dmbpy)2(PPh3)(OH2)](OPh)2 (C monomer) were synthesized and characterized by spectroscopic and electrochemical methods, and they were utilized in construction of new modified electrodes (MEs) and applied in electrooxidation of organic substrates. The preparation of these new MEs was done by coating the surfaces of carbon felt and carbon rod electrodes by polymeric films where the ruthenium complexes were anchored. The potential range applied to accomplish the polimerization of the complexes corresponds to the potencial ranges of diphenol anion and azoic ligand with the phenolic group, respectively. The catalytic activity of these MEs was studied by kinetic methodology monitoring the heterogeneous electroxidations by UV/Vis of some organic substrates like: safrol, isosafrol, benzylic alcohol, phenil ethyl alcohol, ethyl benzene, toluene, cycle-hexen-2-ol, showing that these EMs can be utilized as catalyst in electrooxidations reactions with goods yields.

Neste trabalho os complexos cis- [Ru(BAF)(bpy)(PPh3)(OH2)](ClO4)2 (monômero B) e cis-[Ru(dmbpy)2(PPh3)(OH2)](OPh)2 (monômero C) foram sintetizados e caracterizados através de métodos espectroscópicos e eletroquímicos, sendo utilizados na construção de novos eletrodos modificados EMs e aplicados na eletrooxidação de substratos orgânicos. A preparação destes EMs consistiu no recobrimento da superfície de eletrodos de feltro de carbono e de bastões de grafite pelos filmes poliméricos ancorados ao rutênio. Os intervalos de potencial aplicados para a polimerização dos complexos foram àqueles correspondentes, respectivamente, aos potenciais de polimerização do contra-íon difenolato e do ligante azóico contendo o grupamento fenol. A atividade catalítica destes EMs foi investigada através de um estudo cinético, através de eletrooxidações heterogêneas acompanhadas por UV/Vis de diversos compostos orgânicos como: safrol, isosafrol, álcool benzílico, fenil etil álcool, etil benzeno, tolueno, benzaldeído, ciclo hexen-2-ol, demonstrando que os EMs podem ser utilizados como catalisadores em reações de eletrooxidações com rendimentos satisfatórios. / In this work the complexes cis-[Ru(BAF)(bpy)(PPh3)(OH2)](ClO4)2 (B monomer) and cis-[Ru(dmbpy)2(PPh3)(OH2)](OPh)2 (C monomer) were synthesized and characterized by spectroscopic and electrochemical methods, and they were utilized in construction of new modified electrodes (MEs) and applied in electrooxidation of organic substrates. The preparation of these new MEs was done by coating the surfaces of carbon felt and carbon rod electrodes by polymeric films where the ruthenium complexes were anchored. The potential range applied to accomplish the polimerization of the complexes corresponds to the potencial ranges of diphenol anion and azoic ligand with the phenolic group, respectively. The catalytic activity of these MEs was studied by kinetic methodology monitoring the heterogeneous electroxidations by UV/Vis of some organic substrates like: safrol, isosafrol, benzylic alcohol, phenil ethyl alcohol, ethyl benzene, toluene, cycle-hexen-2-ol, showing that these EMs can be utilized as catalyst in electrooxidations reactions with goods yields.