The general theory of multistage geminate reactions of isolated pairs of reactants. III. Two-stage reversible dissociation in geminate reaction A + A ↔ C ↔ B + B.

Specific two-stage reversible reaction A + A ↔ C ↔ B + B of the decay of species C reactants by two independent transition channels is considered on the basis of the general theory of multistage reactions of isolated pairs of reactants. It is assumed that at the initial instant of time, the reacting system contains only reactants C. The employed general approach has made it possible to consider, in the general case, the inhomogeneous initial distribution of reactants, and avoid application of model concepts of a reaction system structure (i.

General theory of the multistage geminate reactions of the isolated pairs of reactants. II. Detailed balance and universal asymptotes of kinetics.

The analysis of general (matrix) kinetic equations for the mean survival probabilities of any of the species in a sample (or mean concentrations) has been made for a wide class of the multistage geminate reactions of the isolated pairs. These kinetic equations (obtained in the frame of the kinetic approach based on the concept of "effective" particles in Paper I) take into account various possible elementary reactions (stages of a multistage reaction) excluding monomolecular, but including physical and chemical processes of the change in internal quantum states carried out with the isolated pairs of reactants (or isolated reactants). The general basic principles of total and detailed balance have been established.

General theory of multistage geminate reactions of isolated pairs of reactants. I. Kinetic equations.

General matrix approach to the consideration of multistage geminate reactions of isolated pairs of reactants depending on reactant mobility is formulated on the basis of the concept of "effective" particles. Various elementary reactions (stages of multistage reaction including physicochemical processes of internal quantum state changes) proceeding with the participation of isolated pairs of reactants (or isolated reactants) are taken into account. Investigation has been made in terms of kinetic approach implying the derivation of general (matrix) kinetic equations for local and mean probabilities of finding any of the reaction species in the sample under study (or for local and mean concentrations).

Theory of reversible associative-dissociative diffusion-influenced chemical reaction. II. Bulk reaction.

A many-particle homogeneous reacting system of reactants, where bulk reversible reaction A + B ↔ C takes place, is considered in the framework of the kinetic theory approach. The various forms of kinetic equations in the thermodynamic limit are obtained, and important relations between kinetic coefficients characterizing the course of bulk and the corresponding geminate reactions are established. Based on the kinetic equations derived, different results available in the literature have been analyzed.

Theory of reversible associative-dissociative diffusion-influenced chemical reaction. I. Geminate reaction.

A many-particle, in the general case, inhomogeneous reacting system of independent pairs of reactants, where geminate reversible reaction A+B⇄C takes place, is considered in the framework of the kinetic theory approach. The kinetic equations in the thermodynamic limit are obtained, and important relations between kinetic coefficients characterizing the reaction course are established, as well as the relations between the kinetic dependencies under different initial conditions including the relations that extend the familiar literature results to the case of rather realistic model of the reacting system. Universal long-term kinetic laws of the reaction course are determined.

Manifestation of macroscopic correlations in elementary reaction kinetics. II. Irreversible reaction A+B→C.

The applicability of the Encounter Theory (ET) (the prototype of the Collision Theory) concepts for widely occurring diffusion assisted irreversible bulk reaction A+B→C (for example, radical reaction) in dilute solutions with arbitrary ratio of initial concentrations of reactants has been treated theoretically with modern many-particle method for the derivation of non-Markovian binary kinetic equations. The method shows that, just as in the reaction A+A→C considered earlier, the agreement with the Encounter Theory is observed when the familiar Integral Encounter Theory is used which is just a step in the derivation of kinetic equations in the framework of the method employed. It allows for two-particle correlations only, and fails to consider the correlation of reactant simultaneously with a partner and with a reactant in the bulk.

Manifestation of macroscopic correlations in elementary reaction kinetics. I. Irreversible reaction A+A-->product.

Using an modern many-particle method for the derivation of non-Markovian binary kinetic equations, we have treated theoretically the applicability of the encounter theory (ET) (the prototype of the collision theory) concepts to the widely known diffusion assisted irreversible bulk reaction A+A-->product (for example, radical reaction) in dilute solutions. The method shows that the agreement with the ET is observed when the familiar integral ET is employed which in this method is just a step in the derivation of kinetic equations. It allows for two-particle correlations only, but fails to take account of correlation of reactant simultaneously with the partner of the encounter and the reactant in the bulk.