Charge-induced dipole

Induction of electric charge occurs when a charge on one object causes a change in the distribution of charge on a nearby object. Rubbing a balloon to make it "stick" to a wall is an example of charging by induction. There are two types of charge-induced dipole forces. 

Electrostatic interactions encompass ionic, dipole-t ii ., dipole-induced dipole, or charge-induced dipole interactions. No fo-aial elaboration of the appropriate equations will be given here becujis the alkyl bonded stationary phases most commonly used in RPC are no, expected... 

The potential of mean force due to the solvent structure around the reactants and equilibrium electrolyte screening can also be included (Chap. 2). Chapter 9, Sect. 4 details the theory of (dynamic) hydro-dynamic repulsion and its application to dilute electrolyte solutions. Not only can coulomb interactions be considered, but also the multipolar interactions, charge-dipole and charge-induced dipole, but these are reserved until Chap. 6—8, and in Chaps. 6 and 7 the problems of germinate radical or ion pair recombination (of species formed by photolysis or high-energy radiolysis) are considered. 

To show this connection, consider an ion-pair as above (Sect. 2.1). Not only may the ion-pair diffuse and drift in the presence of an electric field arising from the mutual coulomb interaction, but also charge-dipole, charge-induced dipole, potential of mean force and an external electric field may all be included in the potential energy term, U. Both the diffusion coefficient and drift mobility may be position-dependent and a long-range transfer process, Z(r), may lead to recombination of the ion-pair. Equation (141) for the ion-pair density distribution becomes... 

Both the n independence and the 1/v dependence of the cross section agree with a description based on the perturber s scattering from the Li+ core. Since the electron is not involved, the cross section is n independent, and the charge-induced dipole interaction leads to a 1/v dependence of the cross section. Furthermore, the measured rate constants are in good agreement with those computed for the scattering of Li+ from the perturbers, as shown in Table 11.2. 

The induced dipole moment depends on the electric field strength and the structure of the molecule. Charge-induced dipole interactions occur between a charged ion and polarized molecules. A molecule possessing conjugated double bonds is readily polarized. Examples of solutions due to the dipole-induced dipole interaction are benzene in methanol, chloral hydrate in CC14, and phenol in mineral oil. 

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