Dynamic Orientation of Conjugated Oligomers in Nematic Liquid Crystalline Matrices

Polarized photoluminescence is observed from a host/guest system consisting of conjugated oligomers dissolved in nematic liquid crystalline matrices. In this system, conjugated oligomers (guest) exhibit an emission spectrum well separated from the emission of the liquid crystalline matrix (host) however polarized parallel to the orientation of the host matrix. The results clearly demonstrate the spontaneous orientation of the oligothiophenes along the director of the nematic matrix. Upon applying an electric field perpendicular to the direction of the spontaneous orientation, the oligomers are dynamically reoriented (switched) with the host resulting in switching of the polarized photoluminescence.