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Diffusion-Limited Coalescence and Annihilation in Random Media

Catalin Mandache·Daniel ben-Avraham
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Abstract

We study the kinetics of diffusion-limited coalescence, A+A->A, and annihilation, A+A->0, in random media consisting of disconnected domains of reaction. Examples include excitons fusion and annihilation in porous matrices and along polymer chains. We begin with an exact analysis of A+A->A in a finite segment. This result is applied to coalescence in a random distribution of segment lengths, and the implications for coalescence and annihilation in percolation clusters and other confined geometries are then derived by means of scaling techniques.

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Catalin Mandache, Daniel ben-Avraham. 1999-11-03. Diffusion-Limited Coalescence and Annihilation in Random Media. https://doi.org/10.1063/1.481365

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