ELECTROSTATIC RIGIDITY OF POLYELECTROLYTES FROM REPARAMETRIZATION INVARIANCE

The persistence length l(p) of a polyelectrolyte chain can be represen ted as l(p) = l(0) + l(e) where l(0) is the bare persistence and l(e) is the electrostatic contribution coming from the effects of electrost atic chain self-interactions. Using a reparametrization-invariant path integral model of semiflexible polymers we find that I-e depends on t he ionic strength I as l(e) similar to I--1/2. This result accords wit h experimental observations and recent Monte Carlo simulations. Repara metrization-invariance is apparently an essential constraint in select ing acceptable models of semiflexible polymers.