Induction interaction orientation-dependence

Dipole-Dipole Interaction. The first of the four terms in the total electrostatic energy depends on the permanent dipole moment of the solute molecule of radius a (assuming a spherical shape) immersed in a liquid solvent of static dielectric constant D. The function f(D) = 2(D - l)/(2D + 1) is known as the Onsager polarity function. The function used here is [f(D) — f(n2)] so that it is restricted to the orientational polarity of the solvent molecules to the exclusion of the induction polarity which depends on the polarizability as of the solvent molecules, related to the slightly different Debye polarity function q>(n2) according to... 

Theoretical formulations of reorganization in the course of electron-transfer processes have undergone a number of advances in recent years. The relative importance of various solvent contributions (including translational as well as orientational response, and inductive and dispersion as well as elecrostatic interactions) can depend strongly on the polarity (i.e., dipolar, higher multipolar, or nonpolar) as well as other molecular features of the solvent [21, 47-49]. Molecular-level perspectives on solvent response are of great utility in helping to parameterize effective cavity models (e.g., in conjunction with conventional [50] or spatially nonlocal [47] dielectric models). Additivity relationships traditionally assumed to pertain to sol-... 

The interaction of the carbon dioxide molecule with the sieve includes electrostatic, induction, dispersion, and repulsion contributions. The CO2 molecule was assumed to be capable of free rotation, so that the directional interactions could be averaged over all orientations using a Boltzmann weighting factor (JJ) this causes the electrostatic ion-quadrupole interaction to depend on the temperature. Mean values were used for the polarizability (a), the diamagnetic susceptibility (x), and the equilibrium radius of the CO2 molecule. Using vector summation for the total electric field at the CO2 molecule, the total potential, c(r), at a given position r is given by ... 

The van der Waals forces represent an averaged dipole-dipole interaction, which is a superposition of orientation interactions (between two permanent dipoles, Keesom 1913), induction interaction (between one permanent dipole and one induced dipole, Debye 1920) and dispersion interaction (between two induced dipoles, London 1930). The interaction between two macroscopic bodies depends on the geometry of the system (see Fig. 3). For a plane-parallel film with uniform thickness, h, from component 3 located between two semi-infinite... 

Other expressions for these so-called asymptotic intermolecular potentials are available for dipole pole cases, etc., including explicit orientation-dependent terms. A simple example is the interaction of an ion with a molecule that has a permanent dipole moment fj,. In this case, the induction energy (2.17) has an extra term, /z E, where E is the field of the ion, which is in the direction of the relative position vector R and the dot represents the scalar product of two vectors. Using the angle y between the permanent dipole and the relative separation ... 

Whereas the electrostatic forces arising from permanent moments can be attractive or repulsive (depending on orientation), the induction forces are intrinsically attractive. In the large-R limit, these interactions are generally negligible (i.e., of... 

Lipophilicity is a molecular property experimentally determined as the logarithm of the partition coefficient (log P) of a solute between two non-miscible solvent phases, typically n-octanol and water. An experimental log P is valid for only a single chemical species, while a mixture of chemical species is defined by a distribution, log D. Because log P is a ratio of two concentrations at saturation, it is essentially the net result of all intermolecular forces between a solute and the two phases into which it partitions (1) and is generally pH-dependent. According to Testa et al. (1) lipophilicity can be represented (Fig. 1) as the difference between the hydrophobicity, which accounts for hydrophobic interactions, and dispersion forces and polarity, which account for hydrogen bonds, orientation, and induction forces ... 

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