ELECTRICAL AND OPTICAL-PROPERTIES OF PHENYLENE VINYLENE OLIGOMERS OBTAINED BY VACUUM EVAPORATION

Optical absorption, photoluminescence and electrical impedance of phen ylene vinylene (PV) oligomer films deposited onto indium-tin oxide (IT O) substrates by evaporation in vacuum were studied in a wide range of temperatures (10-450 K) and a.c. frequencies (0.3-10(5) Hz). The mate rial possesses an optical band of 2.8 eV, Photoluminescence spectra ar e Stokes shifted for 0.2 eV with respect to absorption and excitement luminescence. A.c. electrical properties of the material show some tem perature-dependent hysteresis of the real part of dielectric permittiv ity, as well as several relaxation/conduction modes at low (-100 to -5 0 degrees C) and high (above 60 degrees C) temperatures.