The transport properties of mixed salts based on CsH2PO4 are influenced by the interactions among charge carriers.

We review and generalize a recent theoretical framework that provides a sound physicochemical basis to describe how volume and surface diffusion are affected by adsorption and desorption processes, as well as by catalytic conversion within the space defined by the irregular geometry of the pores in a material. The theory is based on two single-dimensional mass conservation equations for irregular domains deduced for the volumetric (bulk) and surface mass concentrations. It offers a powerful tool for analyzing and modeling mass transport across porous media like zeolites or artificially build materials, since it establishes how the microscopic quantities that refer to the internal details of the geometry, the flow and the interactions within the irregular pore can be translated into macroscopic variables that are currently measured in experiments. The use of the theory in mass uptake experiments is explained in terms of breakthrough curves and effective mass diffusion coefficients which are explicitly related to the internal geometry of the pores.

Three discotic liquid-crystalline binary mixtures, characterized by their extent of bidispersity in molecular thickness, were investigated with molecular dynamics simulations. Each equimolar mixture contained A-type (thin) and B-type (thick) discogens. The temperature-dependence of the orientational order parameter reveals that A-type liquid samples produce ordered phases more readily, with the (hexagonal) columnar phase being the most structured variant. Moderately and strongly bidisperse mixtures produce globally-segregated samples for temperatures corresponding to ordered phases; the weakly bidisperse mixture displays microheterogeneities. Ordered phases in the B-type liquid are induced partially by the presence of the A-type fluid. In the moderately bidisperse mixture, order is induced through orientational frustration: a mixed prenematic-like phase precedes global segregation to yield nematic and columnar mesophases upon further cooling. In the strongly bidisperse mixture, order is induced less efficiently through a paranematic-like mechanism: a highly-ordered A-type fluid imparts order to B-type discogens found at the interface of a fully-segregated sample. This ordering effect permeates into the disordered B-type domain until nematic and columnar phases emerge upon further cooling. At sufficiently low temperatures, all samples investigated exhibit the (hexagonal) columnar mesophase.

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The change in entropic restrictions in a superprotonic transition controls the increase of the ionic conductance in ionic solids.