Molecular Crystals and Liquid Crystals, Vol.496, 269-277, 2008
Photodielectric Properties of C-60 Solution in the Ferroelectric Liquid Crystal
Within the range Of 10(-3)-10(6)Hz, we investigated the frequency dependences of capacity C and resistance R of a 3 wt% solution of C-60 with attached molecules of 1,8-octanediamine in a ferroelectric liquid crystal (FLC/C60-Ok). The measurements were carried out in darkness and on the exposure to focused white light. The basic feature of the electric properties of solutions of FLC/C-60-Oc is a reduction of the ac conductivity sigma(AC) at the transition from the cholesteric to smectic phase. The measurements have shown that the ratio C-P/C-D (the subscripts D and P correspond, respectively, to measurements in darkness and under illumination) has a peak at a frequency of approximate to 3.5 Hz, and the ratio R-D/R-P increases monotonously up to a constant value within the range of 10(-3)-10(3) Hz. These data indicate that the volumetric photoelectric processes are more essential than the near-electrode ones in the solution FLC/C-60-Oc as compared with the colloidal mixture C-60 + C-70/FLC.