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DY: Fachverband Dynamik und Statistische Physik

DY 5: Soft matter

DY 5.2: Vortrag

Montag, 23. März 2009, 15:00–15:15, ZEU 255

Self-assembling network and bundle structures in systems of rods and crosslinkers — Raghunath Chelakkot¹, Reinhard Lipowsky², and •Thomas Gruhn³ — ¹Institut für Festkörperforschung, Forschungszentrum Jülich, D-52428 Jülich — ²MPI for Colloids and Interfaces, Science Park Golm, D-14424 Potsdam — ³Johannes Gutenberg Universität Mainz, Inst. f. Anorg. u. Analyt. Chemie, D-55099 Mainz

Self-assembling structures are studied in a binary system of long and short spherocylinders. The short spherocylinders have an adhesive site on both ends with which they can bind to the long spherocylinders. In this way, they act as crosslinkers that may interconnect a pair of long rods. In a similar way, network structures are formed by crosslinked actin filaments in the cytoskeleton of living cells. With the help of Monte Carlo simulations, the structure of crosslinker-mediated rod assemblies has been studied systematically and the critical behavior at the percolation threshold has been studied. The system shows a complex phase behaviour, including the formation of bundles of parallel rods and a transition to a three-dimensional, low-densitiy network. Bundles occur both in percolated and non-percolated systems. The same observations have been made for crosslinked actin filament networks in living cell. In a certain range of rod and crosslinker concentrations, the amount of bundling rods is a non-monotonic function of the adhesive strength.