A TEST OF THE BOUNDARY DOUBLING METHOD FOR THE NUMERICAL-SOLUTION OF DIFFUSION-REACTION SYSTEMS

Numerical methods for solving diffusion-influenced bimolecular reactio ns in the 1- and 3-dimensional Smoluchowski approach are presented. Th e finite-difference method is used to solve diffusion-reaction equatio ns for the pair distribution function. The kinetic equation for the co ncentration is evolved by the Runge-Kutta method with an adaptive time step. The boundary doubling method is introduced to study long-time d ynamics where the truncation problem of the infinite boundary is cruci al. The results show remarkable accuracy and speed with small number o f spatial grid points until long times. (C) 1998 Published by Elsevier Science B.V. All rights reserved.