Molecular conformation and orientation of silicon organic photoconductor films

The conformational state and orientation of the films of poly(di-n-hexylsilane) (PDHS) were investigated in dependence on their annealing at the temperature over the temperature of the phase transition with the use of absorption (20-140)degreesC and luminescence (5 K) spectra. The appearance of two new bands in the absorption spectra of the polymer in the region of the gauche conformation is explained with the formation of liquid crystal phase. The alignment of the PDHS backbones was confirmed by the study of orientation of liquid crystal on the surface of the annealed polymer film. Increasing orientational order and defects created during the cooling of the polymer film result in appearance of several new bands in the films absorption spectra after their cooling down to the room temperature.