Benzene-lecithin interaction in lecithin-benzene solutions part II: Optical studies and quantum mechanical calculations☆

Abstract UV absorption and CD spectra of dipalmitoyl- sn -glycerine phosphatidylcholine (DPPC)-benzene and DPPC-cyclohexane systems at different temperatures (in the micellar and gel state) as well as quantum chemical calculations of a benzene-trimethyl ammonium supermolecule demonstrate that in the gel of the DPPC-benzene system a molar fraction of benzene molecules forms a weak charge transfer complex with the -N + (CH 3 ) 3 moiety of DPPC. In the gel state there exists a second fraction of benzene molecules, the reorientation freedom of which is restricted by a liquid crystal-like structure.