DETERMINATION OF DIELECTRIC-RELAXATION TIME OF LANGMUIR-FILMS BY A WHOLE-CURVE METHOD USING THE MAXWELL DISPLACEMENT CURRENT

A whole-curve method using the Maxwell displacement current (MDC) is p resented for determining the dielectric relaxation time tau of floatin g monolayers on the water surface. The dielectric relaxation, time of 4-cyano-4'-alkyl-biphenyle (5CB) monolayers was examined. It was revea led that the dielectric relaxation time tau of 5CB monolayers depends on the molecular area, and shows a good agreement with the theoretical relaxation time in the isotropic polar orientational phase, which was calculated using a rodlike columnar molecule model.