Relaxation processes in Langmuir films under lateral compression

Abstract

The orientational relaxation process of the director n to its equilibrium orientation n(eq), in the Langmuir film, during the lateral compression in absence of flow, is investigated. The relaxation time, during compression of 4-n-pentyl- 4(') -cyanobiphenyl monolayer (multilayer) films on the water surface, using the Ericksen-Leslie theory, has been calculated for a number of dynamic regimes. It is also shown that the viscous and electric forces exerted per unit volume of the monolayer Langmuir film may excite the solitary wave propagating along the air-water interface.