Diffusion-controlled first contact of the ends of a polymer: crossover between two scaling regimes.

Department of Physics, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Physical Review E (Impact Factor: 2.31). 10/2005; 72(3 Pt 1):031804. DOI: 10.1103/PhysRevE.72.031804
Source: PubMed

ABSTRACT We report on Monte Carlo simulations of loop formation of an ideal flexible polymer consisting of N bonds with two reactive ends. We determine the first-passage time associated with chain looping that yields a conformation in which the end monomers are separated by a distance a--the reaction radius. In particular, our numerical results demonstrate how this time scale crosses over from tau(first) approximately N(3/2)/a to the a-independent tau(first) approximately N2 as N is increased. The existence and characteristics, of the two scaling regimes and the crossover between the two, are further illuminated by a scaling argument.

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