We calculate the cyclization rate k(t) of a single polymer chain with charg
ed end groups, where cyclization takes place with probability of one when t
he ends approach each other at a distance smaller than the reaction radius
R. Using Monte Carlo simulations in a kink-jump model we show that the long
-time asymptotic value of k for longer chains and attractive Coulomb intera
ction does not depend on R, but depends strongly on the Onsager radius, whi
ch characterizes the strength of electrostatic interaction. This result rel
ies only on the large-scale behavior of the chain and is reproduced within
a simple harmonic-spring approximation. The harmonic-spring model leads to
a diffusion equation which is solved numerically. The solution for long cha
ins is confirmed with analytical approximations. (C) 2001 American Institut
e of Physics.