Regensburg 2007 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 15: Diffusion and Transport Processes
CPP 15.5: Talk
Tuesday, March 27, 2007, 15:45–16:00, H47
Modelling polyelectrolyte dynamics: The importance of hydrodynamic interactions — •Kai Grass1 and Christian Holm1,2 — 1Frankfurt Institut for Advanced Studies, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main, Germany — 2Max-Planck-Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Germany
In this contribution, we investigate the dynamical properties of short strongly charged polyelectrolytes by means of coarse-grained molecular dynamics simulations. By comparing a purely implicit treatment of the solvent with a Lattice Boltzmann modelled fluid, we show that hydrodynamic interactions have to be included to model the experimentally observed behaviour.
We compare the obtained results to recent experimental studies and illustrate the decisive features, such as the non-monotonic behaviour of the electrophoretic mobility on short length scales and the well-known transition to the free-draining regime. Additionally, we use the obtained diffusion and mobility coefficients to calculate estimates for the effective charge and hereby check the validity of the available theories for charge condensation.
All transport coefficients were obtained at zero and low-field conditions, respectively, in order to not perturb the counter ion cloud, and thus match experimental conditions closely.