Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

BP: Fachverband Biologische Physik

BP 9: Membranes and Interfaces

BP 9.9: Vortrag

Dienstag, 26. Februar 2008, 12:45–13:00, PC 203

Effective potential for a fluctuating membrane between two walls — •Ana-Suncana Smith — II. Institut für Theoretische Physik, Universiät Stuttgart

Lipid membranes, due to their weak curvature elasticity, typically exhibit large out of plane fluctuations. In the vicinity of the substrate, it is the balancing of the attractive van der Waals potential against the bending deformations of the membrane and the steric repulsion arising from fluctuations, which determines the effective potential between the substrate and the membrane. The difficulty is that the effective potential is coupled to the fluctuation amplitude, which thus must be determined self-consistently. Exact solution of this problem has so far been found only in the vicinity of the unbinding transition (Lipowsky, R.; Leibler, S. Phys. Rev. Lett. 1986, 56, 2541). However, the shape of this potential away from the transition has not been calculated yet. We here present an approximate analytic model for the effective potential. We concentrate particularly on the case when the membrane is placed between two walls, and explore the shape of effective potential for a variety of direct interaction potentials.