3 research outputs found
Dynamics of diffusion controlled chain closure: flexible chain in presence of hydrodynamic interaction
Based on the Wilemski-Fixman approach (J. Chem. Phys. 60, 866 (1974)) we
showed that for a flexible chain in theta solvent hydrodynamic interaction
treated with an pre-averaging approximation makes ring closing faster if the
chain is not very short. Only for a very short chain the ring closing is slower
with hydrodynamic interaction on. We have also shown that the ring closing time
for a chain with hydrodynamic interaction in theta solvent scales with the
chain length (N) as N^(1.527), in good agreement with previous renormalization
group calculation based prediction by Freidman et al. (Phys. Rev. A. 40, 5950
(1989))
Dynamics of end to end loop formation for an isolated chain in viscoelastic fluid
We theoretically investigate the looping dynamics of a linear polymer
immersed in a viscoelastic fluid. The dynamics of the chain is governed by a
Rouse model with a fractional memory kernel recently proposed by Weber et al.
(S. C. Weber, J. A. Theriot, and A. J. Spakowitz, Phys. Rev. E 82, 011913
(2010)). Using the Wilemski-Fixman (G. Wilemski and M. Fixman, J. Chem. Phys.
60, 866 (1974)) formalism we calculate the looping time for a chain in a
viscoelastic fluid where the mean square displacement of the center of mass of
the chain scales as t^(1/2). We observe that the looping time is faster for the
chain in viscoelastic fluid than for a Rouse chain in Newtonian fluid up to a
chain length and above this chain length the trend is reversed. Also no scaling
of the looping time with the length of the chain seems to exist for the chain
in viscoelastic fluid