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A method to determine the surface azimuthal anchoring energy of a nematic liquid crystal is proposed. The technique implies the measurement of the director deviation on the cell substrate as a fbnction of strength and direction of the applied magnetic field. As an example, the dependence of the azimuthal anchoring coefficient on the exposure time is measured at the interface between the nematic K15 and polyvinylcinnamate film exposed by UV light. The analogous measurements performed in a wedge cell show that the method with magnetic field is more precise.

The polyvinylcinnamate modified by the partial substitution of side chains for stearoyl fragments has beeninvestigated. An oblique liquid crystal alignment with pretilt angle values controlled by the concentration of the stearoyi groups is obtained. The double degeneracy ofan easy axis indUCed by polarized-light-irradiation technique is also verified.

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