OPTICAL ANISOTROPY AND ORIENTATION ORDER OF UNIAXIAL FILMS OF CONJUGATED POLYMERS

Aver'yanov, E. M. LIQUID CRYSTALS AND THEIR APPLICATION. DOI: 10.18083/LCAppl.2020.1.53

The uniaxial film of conjugated polymer with macromolecules as a set of subunits of different lengths was studied. For this film, the connection between the components ε(1,2)j(ω) of the dielectric function εj(ω) = ε1j(ω) + iε2j(ω) and the orientation order parameter σ was established. The orientation order parameter σ of the dipole moments of molecular transitions corresponds to an isolated absorption band of light with polarization along (j = ||) and across (j = ⊥) the optical axis of the film. New methods have been implemented for determining σ of the P3OT polymer film. The P3OT polymer film is characterized by a planar orientation of subunits and known dependences ε(1,2)j(ω) in the regions of transparency and low-frequency electron absorption. The anisotropy of the components fj(ω) = 1 + Ljj(ω) – 1] of the local-field tensor was taken into account. The experimental values of the components Lj of the Lorentz tensor for the P3OT film were determined using the dependences ε1j(ω) in the visible transparency region. The combined effect of the length and orientation order of the subunits, as well as dynamic dipole-dipole interactions between subunits (local-field effects) on the position of the maxima of the ε2j(ω) bands was shown.