Monte Carlo simulation study of recombination dynamics in solution

Abstract

A Monte Carlo (MC) simulation study of radical recombination dynamics in solution is presented. Random walks on a three-dimensional lattice are used to simulate the diffusion of radical pairs initially prepared by photolysis. The survival probability as a function of time is calculated by the dynamical interpretation of the MC methods. For the dynamics of radical pairs, the interplay of the geminate and the bulk recombinations is important at high concentrations. In most previous simulations only the dynamics of isolated geminate pairs were considered. In our simulations such interplay is clearly demonstrated by studying the intermediate to long time dynamics of many radical pairs. We compare our results with the predictions of the diffusion and the kinetic theories to examine the validity of their approximations. For low concentrations, results of the simulations show good agreement with theoretical predictions and provide a microscopic basis for understanding the recombination process. But notable deviations are found for high concentrations, which can be attributed to the approximations in theoretical studies.

Fundamental Function for the Lattice-based Random Walk Simulation in One Dimension

“…It is well-known that diffusion-influenced reactions can be described by lattice-based random walk Monte Carlo simulations. [1][2][3][4][5][6] Since the continuum limit of the random walk model is closely related to the diffusion process, we can straightforwardly simulate general diffusionreaction systems with the lattice-based Monte Carlo simulation. Although the theories of the random walk on the lattice points have been regularly reported, 1,7 the analytical results for diffusion-reaction systems on lattice points have been relatively rare.…”

Facilitated Protein-DNA Binding: Theory and Monte Carlo Simulation

“…24 An initially implanted particle moves by random walk in 3D lattice. When the particle reaches the cylindrical trap, the trapping occurs if or the binding reaction with the reactive cylinder occurs if .…”

Monte Carlo Simulation Methods for External Field Effects on Diffusion-Influenced Reactions

“…One can see the long time simulation results also agree perfectly with the theoretical predictions of Eq. (12).…”

“…[12][13][14][15][16][17] To study the field effects on diffusionreaction systems, one should make the simulation methods produce consistent results with the known analytical ones of diffusion-reaction equations. The relation between the magnitude of the external field and the hopping probability can be found to utilize the energy difference between lattice points as in the conventional Metropolis method.…”