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Structural features of the glass family xLi2O- yMgO (4.8 Bi2O3 47.6 P2O5) obtained by melt quenching technique were studied taking into account the density, FTIR and UV–vis spectra and also the electrical response observed by impedance spectroscopy. In this work it becomes clarified how the alkaline earth oxides stabilize the glassy matrix and also, the fundamental importance of determining the optimal proportion in order to obtain a flabby easily polarizable matrix to enhance the electrical behavior due to a boosted cation mobility. It is evidenced that when the glass composition becomes complex it is needed to take into account a larger number of structural parameters to understand, to predict or to design the resulting physical properties.

The interactions between the [BMIM][PF6] -ionic liquid- and a phosphate glassy surface is studied through calorimetric, structural and impedance spectroscopy methods. A soft solid conductor material is obtained mixing the ionic glass powder with the ionic liquid in a low proportion (2% and 4%). At microscopic level, the interactions of this ionic liquid with the glassy particle surfaces reveal the formation of new bridging oxygens. Therefore, the material electrical conductivity increases in more than four orders of magnitude. This finding uncovers the essential elements to be considered before incorporating an additional salt to develop a solid electrolyte.

Glasses formed by different oxides are of uppermost importance because they aredeveloped for many applications in electronics, optics, biology, etc. Oxide glasses are built by a three-dimensional network of corner connected oxygen polyhedral that can be modified by the inclusion of other oxides such as transition metal oxides. In this work, the polaron conductivity due to the presence of transition metal oxides in tellurite glasses is analyzed in systems containing alkaline (AO) and alkaline earth oxides (AEO). It is explained how the presence of metal cations (AO or AEO) affects the displacement of the polaron through the network due to the ion-polaron interaction. Fil: Hernandez Garcia, Luis Ancizar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Molina, Magalí Cielo. Universidad Nacional del Sur. Departamento de Química; Argentina Fil: Zoratti, Marianela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Cardillo, Evangelina Cinthia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Terny, Cintia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Sola, Mariela Edith. Universidad Nacional del Sur. Departamento de Química; Argentina Fil: Frechero, Marisa Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina

In this work, the electrical behavior and structural features of the system x Cu 2 O ( 1 − x ) (0.5V 2 O 5 ·0.5MoO 3 ) 2TeO 2 compared to x Ag 2 O ( 1 − x ) (0.5V 2 O 5 ·0.5MoO 3 ) 2TeO 2 (which was already studied) are explored. The main goal is to determine whether the electronic configuration of Cu + and Ag + ions is the key to understand the interactions of these ions with vanadium ions in the glassy matrix studied and to establish the nature of the particular electrical conductivity response. It is shown that despite the fact that both ions (Cu + and Ag + ) have similar electronic configurations but different sizes they have similar electrical behaviors contrary to what is commonly accepted ( i.e. silver modified glasses are completely ionic systems, while copper modified glasses are purely electronic –polaronic- semiconductors). It is expected that both behave as mixed electrical conductors, neither pure polaronic nor pure ionic. It has been found that the minimum observed in the isotherm of conductivity can be explained by the structural features of this glassy matrix and not by a change in its mechanism of conduction.

In this paper, we analyze using differential scanning calorimetry (DSC) how a disordered structure, obtained by the quenching of oxides melted into glass, is related to the nature of the modi- fier cation. We estimated the enthalpy relaxation in based tellurite oxide glasses of formula xM2O (1−x)(0.5 V2 O5 ·0.5MoO3 ) 2TeO2 when they are modified with univalent metal oxides as Na+ , Li+ and Ag+. As ionic conductors in tellurite oxide glasses, these cations have the same charge but different size, electronic configuration and, in addition, their electric behavior is quite different. We show that the jump in the Cp at Tg is also related to the nature of the modifier cation. We study the conventional view of the configurational entropy of liquid that is frozen below the glass transition temperature (Tg) with what is called entropy loss. We explore whether or not there is a relationship between the nature of the modifier oxide and its magnitude. Fil: Cardillo, Evangelina Cinthia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; Argentina Fil: Terny, Cintia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; Argentina Fil: Frechero, Marisa Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; Argentina

In this work, we suggest an explanation of the electrical conductivity behavior of tellurite glassy systems modified with barium when transition metal oxides (V2O5-MoO3) present in the glassy matrix are replaced progressively by barium oxide. These glasses of formula x BaO (1 − x)(0.5 V2O5· 0.5 MoO3)2 TeO2 are obtained by the standard quenching technique and analyzed by means of impedance spectroscopy. We also report some structural results that explain the effect of the bivalent cation (Ba+2) on the electrical response in comparison to the effect of univalent cations on this kind of glassy matrix. The results confirm the existence of a transition from a typical hopping of small polarons response (when the content of BaO is low) to a weak ionic conductive response (when more than 50% of the transition metal oxides content has been replaced by BaO). The independent migration path is suggested by the observed electrical conductivity behavior. In this system, vanadium gives the active centers responsible for the polaron hopping mechanism while barium cations seem to be responsible for the ionic transport regimen. Fil: Terny, Cintia Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Cardillo, Evangelina Cinthia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Di Pratula, Pablo Emmanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Villar, Marcelo Armando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahia Blanca. Planta Piloto de Ingeniería Química (I). Grupo Vinculado al Plapiqui - Investigación y Desarrollo en Tecnología Química; Argentina Fil: Frechero, Marisa Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina

The effect of the partial replacement of lithium oxide by silver oxide in a glassy vanadium-molybdenum-tellurite oxides matrix is analyzed by means of impedance spectroscopy. We find that a weak mixed mobile ion effect (MMIE) is due to the different kind of modifications silver and lithium oxides induce in the glass of formula 0.7[x Ag2O (1 - x) Li2O] 0.3[0.5 V2O5 0.5 MoO3] 2 TeO2. Fil: Cardillo, Evangelina Cinthia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Montani, Ruben Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina Fil: Frechero, Marisa Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina