Elasticity of Lipid Membrane Leaflets: Determining Pivotal Plane and Tilt Modulus in Computer Simulations

This thesis introduces a novel protocol to measure two elastic quantities of lipid membranes, the pivotal plane of a single leaflet and the lipid tilt modulus. The key setup relies on the simulation of a buckled membrane, a configuration that had been previously proposed to measure a membrane's bending rigidity. Since this method solely depends on the geometrical analysis of the membrane shape, and can hence even be applied to existing simulation trajectories of buckled membranes, it can provide two additional physical quantities at no extra simulation cost. Due to the high precision of its result, many technical subtleties are considered throughout the derivation, pertaining for instance to higher order corrections due to Poisson ratio effects. This calculation, as shown in this thesis, can be used to provide both a reference for other study as well as deeper insight into the nature of lipid models, especially the limitation of the coarse-grained ones.