Barrier crossing in one and three dimensions by a long chain

TLDR: In this article, the authors considered the Kramers problem for a long chain polymer trapped in a biased double-well potential and showed that the time of crossing is proportional to the chain length, which is in agreement with the results for the kink mechanism.

Abstract: We consider the Kramers problem for a long chain polymer trapped in a biased double-well potential Initially the polymer is in the less stable well and it can escape from this well to the other well by the motion of its N beads across the barrier to attain the configuration having lower free energy In one dimension we simulate the crossing and show that the results are in agreement with the kink mechanism suggested earlier In three dimensions, it has not been possible to get an analytical 'kink solution' for an arbitrary potential; however, one can assume the form of the solution of the nonlinear equation as a kink solution and then find a double-well potential in three dimensions To verify the kink mechanism, simulations of the dynamics of a discrete Rouse polymer model in a double well in three dimensions are carried out We find that the time of crossing is proportional to the chain length, which is in agreement with the results for the kink mechanism The shape of the kink solution is also in agreement with the analytical solution in both one and three dimensions