Abstract
A method of analyzing small-angle neutron scattering data from polydisperse rodlike micelles is presented and applied to diheptanoylphosphatidylcholine in aqueous solution. This short-chain lecithin forms micelles, which can be modeled by cylinders of minimum size of 27 monomers that grow dramatically in length as the lecithin concentration increases. The thermodynamic theory developed for these particles accounts quantitatively for average micelle size, size distribution, and growth of diheptanoylphosphatidylcholine compared to nongrowing dihexanoylphosphatidylcholine micelles. © 1987 American Chemical Society.