Analytical expressions for the closure probability of a stiff wormlike chain for finite capture radius

T. Guérin (1)

1 LOMA - Laboratoire Ondes et Matière d'Aquitaine

Estimating the probability that two monomers of the same polymer chain are close together is a key ingredient to characterize intramolecular reactions and polymer looping. In the case of stiff wormlike polymers (rigid fluctuating elastic rods), for which end-to-end encounters are rare events, we derive an explicit analytical formula for the probability η(r c) that the distance between the chain extremities is smaller than some capture radius r c. The formula is asymptotically exact in the limit of stiff chains, and it leads to the identification of two distinct scaling regimes for the closure factor, originating from a strong variation of the fluctuations of the chain orientation at closure. Our theory is compatible with existing analytical results from the literature that cover the cases of a vanishing capture radius and of nearly fully extended chains.

Domaines: Mécanique statistique [cond-mat.stat-mech]

T. Guérin. Analytical expressions for the closure probability of a stiff wormlike chain for finite capture radius. Physical Review E , 2017, 96 (2), pp.022501. ⟨10.1103/PhysRevE.96.022501⟩. ⟨hal-01578124⟩