Elastic energy of tilt and bending of fluid membranes

摘要: Tilt of hydrocarbon chains lipid molecules with respect to membrane plane is commonly considered characterize the internal structure a in crystalline state. However, membranes liquid state can also exhibit tilt resulting from packing constraints imposed on diverse biologically relevant structures such as intermediates fusion, pores bilayers and others. We analyze energetics its coupling bending. consider three contributions elastic energy: constant tilt, variation along surface The major assumption model that core has common properties an continuum. show bending are additive their energy determined by same coefficient: Helfrich modulus, modulus Gaussian curvature spontaneous known previous studies pure combined deformation varying effective tensor accounting for two factors. In contrast, does not couple contribution independent constant. While accurate determination this requires additional measurements, we estimate value using simplified approach. discuss relationships between obtained Hamiltonian models elasticity.