الفهرس 
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Abstract
Thin films of 9,10 phenanthrene quinone (PQ) have been successfully deposited by the thermal evaporation technique. The structural investigations on its powder, pristine and annealed thin films are performed using FTIR, DSC, XRD and AFM techniques. PQ films have thermal and chemical stabilities. The powder and thin films of PQ have polycrystalline structure and the grain size of pristine PQ films increases by annealing temperature. The optical constants of PQ films (n and k) have been calculated from spectrophotometer measurements of transmittance and reflectance at nearly normal incidence of light. The optical absorption of PQ films showed indirect allowed transition with onset and optical energy gap as 1.73 and 2.58eV, respectively. Annealing temperature has no effect on optical energy gap but it decreased onset energy gap. The dispersion parameters of PQ films have been calculated and their variation with annealing temperature has been demonstrated. The dielectric functions and their relation to incident light frequency and annealing temperature have been illustrated.
The results of DC conductivity showed that it has a semiconductor behavior and the small activation energies indicate that the conduction is by hopping of charge carriers. The AC conductivity of bulk PQ has been investigated in temperature range 313-368 K and in frequency range 0.5-107.7 kHz. It was found that there are two conduction regions depending on temperature and the activation energy of charge carriers in both regions decrease with increasing frequency. The conduction mechanism under applying a frequency is correlated barrier hopping and the maximum barrier potential is 0.345 eV. The variation of dielectric constant with temperature and frequency has been considered and discussed.