Simple model for diffusive behavior of reactive radical pairs

Abstract

A simple model is derived to account for the diffusive behavior of radical pairs which are destroyed rapidly. The implications of this model are discussed.

Photochemical studies as a function of solvent viscosity. A new photochemical pathway in the reaction of (η5-C5H4Me)2Mo2(CO)6 with CCl4

“…Some cage effect theories suggest that k dP is proportional to η ½ . 19 However, attempts to fit the quantum yield data to a modified form of eqn. (2) containing η n , where n is a variable parameter, did not give a better fit.…”

Solvent cage effect in the photolysis of azomethane in aqueous alcohols and other media: a semiempirical correlation with macroscopic solvent parameters

“…There has been considerable success in treating properties of certain liquids in terms of theoretical models involving a Average of at least two determinations. 6 Values of (CH4 + CH3CO/2C2H6 are reported. hard-sphere molecules.50a•51 For a solute molecule such as the methyl radical, which is not expected to show important specific interactions with hydrogen-bonding solvents, we can view the motions of the solute molecules, even in associated solvents, in very similar terms and develop a model for diffusion starting from kinetic gas theory.…”

“…In the case of an imperfect gas, (dE/dV)r becomes appreciable, and in the case of a liquid it may become much greater than the external pressure, with typical values lying between 2000 and 5000 atm. Thus at 1 atm the external pressure (P) can be neglected in comparison with P\ so that eq 4 becomes Journal of the American Chemical Society / 98:21 j October From eq 3, the expression for the diffusion coefficient of a liquid molecule may now be written as D = 0.6 cRTv PiV2!3 (6) In a liquid in which diffusive displacements of solvent molecules are truly random, the average velocity is given4 by v = (8 RThrM)'!2 (7) where M is the molecular weight of the solvent. Thus eq 6 becomes…”

Intermolecular force effects on geminate combinations

“…A-X-B -A||B the bulk properties of the medium. (2) All other complications such as, e.g., discussed by Carapellucci8 are ignorable for the systems to which we restrict our considerations. (3) All separations between the fragments can be treated as if they occurred along a straight line connecting the center of mass of A and B in case I and an effective straight line connecting the centers of mass of A, X, and B in case II.…”