Charge-dipole interaction model

A charge-dipole interaction model has also been used [27] recently for the calculation of the freqnency-dependent polarizability of silver clnslers. Time variations of the atomic charges are shown to be related to the cnrrents that flow through... 

This fomuila does not include the charge-dipole interaction between reactants A and B. The correlation between measured rate constants in different solvents and their dielectric parameters in general is of a similar quality as illustrated for neutral reactants. This is not, however, due to the approximate nature of the Bom model itself which, in spite of its simplicity, leads to remarkably accurate values of ion solvation energies, if the ionic radii can be reliably estimated [15],... 

There is thus an apparent continuity between the kinetics of an electron transfer leading to a stable product and a dissociative electron transfer. The reason for this continuity is the use of a Morse curve to model the stretching of a bond in a stable product in the first case and the use of a Morse curve also to model a weak charge-dipole interaction in the second case. We will come back later to the distinction between stepwise and concerted mechanisms in the framework of this continuity of kinetic behavior. 

Figure 40. Mobility (/i, plotted as In//) vs. field strength ( , plotted on a scale proportional to as predicted by the Correlated Disorder Model for DOS of various r.m.s. widths a. The disorder is assumed to arise purely from random charge-dipole interactions. The lattice parameter is a. For a = lOA and = 0.1 eV, eaEja = 1 corresponds to a field strength of 10 V cm. (Reprinted with permission from Ref [63f].)...

POL and POLl have the same three-site tetrahedral, SPC-like geometry with a charge on each site. The charge magnitude is adjusted to reproduce properties of the liquid, and the resulting dipole, 2.024 D, is much closer to the value in gas phase than for effective non-polarizable models. Polarizability, described by atomic polarizabilities obtained from the atom-dipole interaction model of Applequist et al [172] is however underestimated. POLl modifies the... 

The model has been improved by Novikov et al. [96], who showed that the dominant source of diagonal disorder is due to charge-dipole interactions and that spatial correlations of such interactions need to be taken into account in order to explain the commonly observed Poole-Frenkel dependence of the mobility on the electrical field. These researchers derived an expression for the electric field (E) and... 

In MM3 the option exists to compute charge-charge and charge-dipole interaction energies between ions and between ions and polar molecules. The values for the bond dipoles were chosen to reproduce the molecular dipole moments for test molecules. It has been demonstrated that bond dipoles may be derived to reproduce the quantum mechanical molecular electrostatic potential (ESP) and that a dipole model can perform as effectively as the more common partial atomic charge model derived from the same potential.The... 

The MR term is the contribution of the indirect effects of the charge interactions, such as the charge-dipole interactions and charge-induced dipole interactions, to the excess Gibbs energy. In the LIQUAC model, the MR term is given by... 

Other investigations using the charge-dipole model include the study of enhanced polarizability of aromatic molecules placed between two silver clusters [32], polarization of fullerenes [28], fullerene clusters [29], silicon clusters [31], and so on. Polarizability of molecular clusters [24] has also been calculated using the dipole interaction model and it would be interesting to investigate the applicability of simple linear scaling relations of polarizability as a function of the cluster size, as obtained by ab initio calculation [56],... 

---