Interactions ion-solvent

The McMillan-Mayer theory offers the most usefiil starting point for an elementary theory of ionic interactions, since at high dilution we can incorporate all ion-solvent interactions into a limitmg chemical potential, and deviations from solution ideality can then be explicitly coimected with ion-ion interactions only. Furthemiore, we may assume that, at high dilution, the interaction energy between two ions (assuming only two are present in the solution) will be of the fomi... 

In the tradition of previous reviews [1-22], this section addresses various aspects of nonaqueous electrolytes, including intrinsic properties, such as local structures caused by ion-ion and ion-solvent interactions and bulk properties, such as ionic conductivity, viscosity, and electrochemical stability (voltage window), and their relationships to intrinsic properties. 

Spectroscopic studies of ion-ion-solvent interaction in solutions containing oxyanions. D. W. 

Frank, H. S. Wen, W-Y. (1957). Structural aspects of ion-solvent interactions in aqueous solutions-water structure. Discussions of the Faraday Society, 24, 133. ... 

In the Born equation, the ion solvent interaction energy is determined only by one physical parameter of the solvent, i.e., the dielectric constant. However, since actual ion-solvent interactions include specific interactions such as the charge-transfer interaction or hydrogen bonds, it is natural to think that the Born equation should be insufficient. It is well known that the difference in the behavior of an ion in different solvents is not often elucidated in terms of the dielectric constant. 

It should be noted, however, that this equation represents the energy for a one-to-one ion-solvent interaction. 

In the proposed theory, short-range ion-solvent interaction energies are formulated as Eq. (31). the coefficients A, B, and C in the quadratic equation are related to coefficients Fj, F2, and F3 in the formula for [Eq. (36)]. The above-mentioned regression... 

Gibbs transfer energy of an ion i from phase a to p AG g Gibbs energy for ion-solvent interaction in phase a A log P partition coefficient difference between two solvent systems A 0 Galvani potential difference between a and p phases Ag(pi/2 half-wave potential... 

Further, in the case of virtually non-existent ion-solvent interactions (low degree of solvation), so that solute-solute interactions become more important, Kraus and co-workers47 confirmed that in dilute solutions ion pairs and some simple ions occurred, in more concentrated solutions triple ions of type M+ X M+ orX M+X andinhighly concentrated solutions even quadrupoles the expression triple ions was reserved by Fuoss and Kraus48 for non-hydrogen-bonded ion aggregates formed by electrostatic attraction. 

For this reason, the emphasis in this article is directed more towards the simulation of specific adsorption and, in particular, the recent encouraging comparison of electrochemical and UHV data for the interaction of bromine and chlorine with Ag 110 /7, 8/. A brief outline of the conclusions emerging from alkali-water coadsorption experiments is given to illustrate basic modes of ion-solvent interaction on metal surfaces and to discuss future directions of this research. 

We shall develop here a simple methodology for the computation of AEins, in terms of the electrostatic potential at nucleus V0. Within this frame, we will show that the first term of Eq (18) represents, in the context of the reaction field theory, the ion-solvent interaction energy. 

We shall now show that the insertion energy may be cast into a form completely equivalent to Bom formula. This may be easily done by using the well known relationship between the electrostatic ion-solvent interaction energy and the electronic polarization energy [3,14], Namely... 

Another subsidiary class of clusters is often referred to as "naked. This class, which includes ions such as Bii+, Snjj-, GeJ- and SnJ-, is largely unexplored, but clearly its chemistry will be dominated by large ion-ion or ion-solvent interactions. Such clusters will not be considered in this account. 

This volume of Modem Aspects covers a wide spread of topics presented in an authoritative, informative and instructive manner by some internationally renowned specialists. Professors Politzer and Dr. Murray provide a comprehensive description of the various theoretical treatments of solute-solvent interactions, including ion-solvent interactions. Both continuum and discrete molecular models for the solvent molecules are discussed, including Monte Carlo and molecular dynamics simulations. The advantages and drawbacks of the resulting models and computational approaches are discussed and the impressive progress made in predicting the properties of molecular and ionic solutions is surveyed. 

As has been previously mentioned, ion-solvent interactions involve several factors that include electrostatic and Lewis acid-base contributions. It would be helpful to be able to estimate the magnitude of the individual contributions from these separate factors, and much effort is being directed toward devising ways of estimating the polarity of solvents. Several methods have been proposed. One empirical approach to the problem involves use of the relation... 

Association and mobilities are related in a complex way to the bulk properties of the solvent and solute. These properties include the charge density and distribution on the ions and the Lewis base properties, the strength and nature of the solvent molecule dipole, the hydrogen-bonding capability, and the intermolecular structure of the solvent. Some correlations can be made on the basis of mobility and association trends in series such as the halides and alkali metals within a single solvent others can be drawn between solvents for a given ion. It appears that conductance measurements provide a clear measure of the sum of ion-solvent interactions, but that other techniques must be used in conjunction with conductance if assessments of individual contributions from specific factors are to be made. 

For an irreversible reduction the half-wave potential is determined not only by the standard electrode potential but also by the polarographic overvoltage. For a simple electrode process the metal ion-solvent interaction is mainly responsible for the polarographic overvoltage and hence E[ j of such irreversible reductions may also be considered as a function of the solvation 119f... 

It was established that ion-solvent interactions are responsible for the high mobility in water, and ion-ion interactions and ion-pair formation also play a considerable role in mobility. 

The application of an organic solvent in CE offers a new possibility to change the selectivity of CE systems. Moreover, the various ion-solvent interactions and ion-pair formations can be exploited for increased separation efficacy. Its application for CE analysis of ionic synthetic dyes may be expected in the future [121],... 

Although simple, a model system containing one solvent molecule together with one ion already provides valuable insight into the nature of the ion-solvent interaction. There is also convincing evidence that this two body potential dominates in much more complicated situations like in the liquid state 88,89,162). Molecular data for one to one complexes can be calculated with sufficient accuracy within reasonable time limits. Gas-phase data reported in Chapter III provide a direct basis for comparison of the calculated results. 

Some of the most important properties of ion-solvent interaction have been studied where water is used as the solvent molecule. Furthermore, these calculations have frequently been made with fairly extended basis sets. Therefore we draw our attention first to hydration studies. 

This is related to the concept of internal pressure, which increases when salt is added to an aqueous solution. The increase in internal pressure resulting from the ion-solvent interaction then squeezes out the nonelectrolyte molecules from the solution. 

In any study of electrosorption of neutral molecules on metallic electrodes, the ions of supporting electrolytes should not be specifically adsorbed. Nevertheless, the interaction of the electrolyte ions with the electrode surface may depend on the interaction of the ions with the solvent. Usually, the stronger the ion-solvent interaction, the weaker the adsorption of the ion. Since the ions are more weakly solvated in nonaqueous solvents than in water, the ions that are not adsorbed from aqueous solutions may still be adsorbed from organic solvents. However, even in the absence of... 

---