Abstract: It was found by means of the small angle X-ray scattering (SAXS),that layer distance of the liquid-crystal system consisting of egg yolk phospholipid (PC) and 5% water changes with the addition of benzene,methylbenzene or chlorobenzene. From this experiment it can be seen that layer distance in 5% H_2O-PC system changes alternatively as the benzene content is increased. It is considered that Water-PC and Benzene-PC bimolecular double layers are formed. As chlorobenzene content is increased, the system is disordered easily. This phenomenon can be explained by the ability of the polar groups and hydro-carbon chain tail of the egg yolk phospholipid being attracted by molecules of chlorobenzene.

Key words: Egg yolk phospholipid, Structure of Liguid-crystal, Small angle X-ray scattering