Small separation between reactants, not exceeding 10−8−10−7cm, is the necessary condition for various chemical reactions. It is shown that random advection and stretching by turbulence leads to formation of scalar-enriched sheets of strongly fluctuating thickness ηc. The molecular-level mixing is achieved by diffusion across these sheets (interfaces) separating the reactants. Since diffusion ti...

Transition states are the balance point of catalysis. Bonds are partially made and/or broken at the transition state, and the energy of the extended system provides near-equal probability that the system forms products or reverts to reactants. Enzymatic catalytic sites provide dynamic electronic environments that increase the probability that the transition state will be formed. Alignment of re...

The mechanism for electron transfer is discussed in terms of an atomic motion on a potential-energy surface in many-dimensional atomic configuration space. In the absencc of electronic coupling between the reactants, a surface for the reactants intersects one for the products. Electronic coupling causes the usual removal of this degcncracy and permits the products to be formed adiabatically or ...

In this paper, influence of crowding by inert particles on the geminate reaction kinetics is theoretically investigated. Time evolution equations for the survival probability of a geminate pair are derived from the master equation taking into account the correlation among all diffusing particles, and the results are compared with those obtained by Monte Carlo simulations. In general, excluded v...

We study the reaction-diffusion process A + B → ∅ with injection of each species at opposite boundaries of a one-dimensional lattice and bulk driving of each species in opposing directions with a hardcore interaction. The system shows the novel feature of phase transitions between localized and delocalized reaction zones as the injection rate or reaction rate is varied. An approximate analytica...

The autoignition of the catalytic reaction of hydrogen/air mixtures on thin palladium wires is analyzed in this paper. The reduced heterogeneous kinetics is modeled with a mechanism that includes the dissociative adsorption of both reactants, together with three surface reactions of the Langmuir–Hinshelwood type, and the desorption reaction of the adsorbed product, H2O(s). We show that for the ...