Monolayers of the amphiphile 1-monopalmitoyl-rac-glycerol at the air−water interface assemble into domains in which the molecular tilt azimuth is organized into star-shaped patterns. When the domains are transferred to solid supports as Langmuir−Blodgett films, they are capable of producing a macroscopic azimuthal orientation of nematic liquid crystals, which allows the order in the monolayer to be observed by polarized optical microscopy.

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When measuring the po larization of a ferroelectric liquid crystal one usually obtains quite a pronounced tail P(T) going well into the SmA *-phase. If this is a manifestation of the elcctrodinic effect one would, at first thought, expect it to scale as P-(T-Tct and as P-E. In reality, however, it scales like P-( T-Tc ( and P-£ 3 . In order to find out whether this is consistent with the Landau description of the transition one has to check the precise character of the quantity P actually furnished by the measurement. A recent theoretical model based on the triangle-wave technique combined with the Landau theory for the temperature dependence of the induced polarization in the SmA *-phase is experimentally verilied in a number of different compounds. Measurements with the bridge method also confirm the model, indicating the equivalence of the bridge and triangle-wave techniques. The concept of measured (observed) polarization as distinguished from polarization as order parameter in the Landau theory, is pointed out and their relation discussed.