Ion transfer energy

The evaluation of the nonelectrostatic term is usually empirical and multifarious. Based on a skillful argument, however, Volkov and coworkers [9,11,12] proposed that the nonelectrostatic term of the ion transfer energy, AGfr Cne), should be expressed by a semiempirical equation called the Uhlig equation [13], which is given by... 

On the assumption that = 2, the theoretical values of the ion solvation energy were shown to agree well with the experimental values for univalent cations and anions in various solvents (e.g., 1,1- and 1,2-dichloroethane, tetrahydrofuran, 1,2-dimethoxyethane, ammonia, acetone, acetonitrile, nitromethane, 1-propanol, ethanol, methanol, and water). Abraham et al. [16,17] proposed an extended model in which the local solvent layer was further divided into two layers of different dielectric constants. The nonlocal electrostatic theory [9,11,12] was also presented, in which the permittivity of a medium was assumed to change continuously with the electric field around an ion. Combined with the above-mentioned Uhlig formula, it was successfully employed to elucidate the ion transfer energy at the nitrobenzene-water and 1,2-dichloroethane-water interfaces. 

More useful, because they can be used to compare reactivities between solvents, are single ion transfer energies. These are a measure of the dif-... 

Table 12.8 Single ion transfer energies for some common anions, AGt(H20 S)/kJ mol 25°C, selected from ref. 11a...

The aim of this chapter is to provide a short review covering the present state of research and knowledge, as well as the problems concerning electrochemistry of liquid interfaces at equihbrium. These systems are best described by mutually related chemical parameters, such as ion transfer energy, A%Gi, and electrical parameters, such as Galvani and Volta potentials, A cp and A%,xp, where s and w refer to the system consisting of organic and aqueous phases mutually saturated. It is well known that both these potentials can be correlated with the difference of surface potentials of the s... 

That the distribution potential of the water-immiscible solvent (in particular, nitrobenzene) system, in the presence of TEAPi distributed between two phases, is close to zero. It can be concluded from the above assumptions that the EMF of cell XII is equal to the value of the distribution potential (defined by Eqs. (14,18-20) of the salt MX. It is noteworthy that salt bridges containing TEAPi were often used, and as mentioned above, both in direct studies of the distribution systems or in measurements of the ion transfer energy, e.g. of Ag, between two miscible or immiscible solvents [116-119]. In some works a bridge with TEAPi in di-isopropyl ketone was most frequently used but unfortunately, different reference interfaces or electrodes, e.g. calomel and picrate electrodes, were employed [48,62]. 

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