We have studied the changes in the orientational distribution functions of azobenzen-labeled polyamic acid monolayers before and after photoisomerization by measuring optical second-harmonic generation (SHG). From the surface SHG data, we determined the nonlinear-optical tensor components of the monolayers before and after the photo-isomerization. It is found that the point symmetry of the azo-pendant units in the monolayer changes from C∞υ to C1υ by the photo-isomerization.
|Number of pages||4|
|Journal||Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals|
|State||Published - 1997|