The Experts below are selected from a list of 27 Experts worldwide ranked by ideXlab platform

Stefan Scheiner - One of the best experts on this subject based on the ideXlab platform.

  • Complexes containing CO2 and So2. Mixed dimers, trimers and tetramers.
    Physical chemistry chemical physics : PCCP, 2014
    Co-Authors: Luis Miguel Azofra, Stefan Scheiner
    Abstract:

    Mixed dimers, trimers and tetramers composed of So2 and CO2 molecules are examined by ab initio calculations to identify all minimum energy structures. While AIM formalism leads to the idea of a pair of C⋯O bonds in the most stable heterodimer, bound by Some 2 kcal mol−1, NBO analysis describes the bonding in terms of charge transfer from O lone pairs of So2 to the CO π* antibonding orbitals. The second minimum on the surface, just slightly less stable, is described by AIM as containing a single O⋯O chalcogen bond. The NBO picture is that of two transfers in opposite directions: one from a So2 O lone pair to a π* antibond of CO2, supplemented by CO2 Olp → π*(So). Decomposition of the interaction energies points to electrostatic attraction and dispersion as the dominant attractive components, in roughly equal measure. The various heterotrimers and tetramers generally retain the dimer structure as a starting point. Cyclic oligomers are favored over linear geometries, with a preference for complexes containing larger numbers of So2 molecules.

Luis Miguel Azofra - One of the best experts on this subject based on the ideXlab platform.

  • Complexes containing CO2 and So2. Mixed dimers, trimers and tetramers.
    Physical chemistry chemical physics : PCCP, 2014
    Co-Authors: Luis Miguel Azofra, Stefan Scheiner
    Abstract:

    Mixed dimers, trimers and tetramers composed of So2 and CO2 molecules are examined by ab initio calculations to identify all minimum energy structures. While AIM formalism leads to the idea of a pair of C⋯O bonds in the most stable heterodimer, bound by Some 2 kcal mol−1, NBO analysis describes the bonding in terms of charge transfer from O lone pairs of So2 to the CO π* antibonding orbitals. The second minimum on the surface, just slightly less stable, is described by AIM as containing a single O⋯O chalcogen bond. The NBO picture is that of two transfers in opposite directions: one from a So2 O lone pair to a π* antibond of CO2, supplemented by CO2 Olp → π*(So). Decomposition of the interaction energies points to electrostatic attraction and dispersion as the dominant attractive components, in roughly equal measure. The various heterotrimers and tetramers generally retain the dimer structure as a starting point. Cyclic oligomers are favored over linear geometries, with a preference for complexes containing larger numbers of So2 molecules.

Ildoo Chung - One of the best experts on this subject based on the ideXlab platform.

Liliana Mogni - One of the best experts on this subject based on the ideXlab platform.

  • Study of phase stability of SrTi0.3Fe0.7O3−δ perovskite in reducing atmosphere: Effect of microstructure
    Solid State Ionics, 2019
    Co-Authors: Mariano Santaya, Lucia Toscani, Laura Baqué, Horacio E. Troiani, Liliana Mogni
    Abstract:

    Abstract Increasing SoFC electrode's surface area by modification of its microstructure is a well-known technique to reduce electrode polarization resistance. This is because reduced grain size and increased porosity promote diffusion and surface reactions, thus improving the electrode performance. However, a modified microstructure alSo causes differences in phase stability and in chemical compatibility with other SoFC materials. In this work, we study the effect of particle size in both the electrode performance and the phase stability under different fuel conditions and temperatures. SrTi0.3Fe0.7O3−δ (STF) is both prepared via Solid state reaction (STF-SSR) and alSo by an alternative Sol-gel route (STF-SG). The sintering temperature is reduced dramatically with the Sol-gel method, hence inducing a higher porosity and a much smaller grain size. As particle size is reduced the stability under fuel conditions is alSo diminished, So Decomposition induced by segregation of metallic Fe and SrO occurs at lower temperatures for the STF-SG sample. The stability under reducing conditions is studied by combined techniques such as TGA, TPR, XRD, SEM and TEM. Performance as anode and cathode is evaluated by Electrochemical Impedance Spectroscopy (EIS) by using electrolyte supported symmetrical cells. Prior to electrochemical experiments, the reactivity between La0.8Sr0.2Ga0.8Mg0.2O3 (LSGM) electrolyte and STF was studied, and alSo between STF and a Lanthanum Doped Ceria (LDC) buffer layer. It is seen that microstructure alSo plays a key role in the chemical stability of the STF. The impact of particle size reduction is higher for the anodic polarization resistance, which is reduced twice from STF-SSR to STF-SG.

Ji Eun Lee - One of the best experts on this subject based on the ideXlab platform.