Phase transitions of lipid bilayers. II. Mean field theory

Abstract

We use the mean field theory of Pink et al. with the ab initio calculations of the density of states of Tevlin et al. to calculate various features of the main phase transition of a lipid bilayer using fewer fitting parameters than in previous models. Good agreement with experiment is obtained for the calculated transition temperature, Gibbs free energy, enthalpy, and average number of gauche rotations per acyl chain. The average chain area is poorly predicted; we expect this to be corrected once cooperative packing of the acyl chains is taken into account. The nematic order along the chain is also calculated and found to agree qualitatively with experiment.