الفهرس 
Theoretical Physical ConceptsOnly 14 pages are availabe for public view
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Abstract
The conventional thermal evaporation technique was used to prepare three Chloroquinoxaline (C1 , C2 and C3 ) thin films under vacuum of 6 x10-6 mbar at room temperature. The structural, optical and electrical transport properties of the films have been investigated. The structural properties were studied using the Fourier transforms infrared spectroscopy (FTIR) and the X-ray diffraction (XRD) techniques, while the Atomic force microscopy was used to study the surface morphology. The infrared absorption spectra showed the thermal stability of the films. XRD results of powder form C1 and C2 demonstrated polycrystalline and amorphous phases. Also, C3 had a completely amorphous phase. According to the results the best solutions for the two compounds showed that they both have monoclinic system but with different space groups and lattice parameters. The (XRD) pattern was also used to determine Miller indices at each peak in the diffraction curve of the powder. The (XRD) patterns for C1 , C2 and C3 in thin film form have been determined. The amorphous phase of all the compounds is confirmed due to the presence of a wide hump. The surface morphology of C1 , C2 and C3 thin films is studied by AFM technique. The thermal properties of the three compounds under test have been investigated by TGA & DSC. It showed that the thermal chemical stability range differs from one derivative to another. The optical properties of thin films were investigated using the spectrophotometric measurements of the transmittance, T(λ), and reflectance, R(λ), at normal incidence of light in the wavelength range 200 - 2500 nm. The data of the transmittance and the reflectance were analyzed to determine the optical constants (the refractive index, n, and the absorption index, k,). The dispersion analysis has been carried out on the as deposited films to obtain the dispersion energy, oscillator energy, the high frequency dielectric constant and the lattice dielectric constant for C1 , C2 and C3 thin films. The absorption analysis has been performed to determine the type of electronic transitions and the optical band gaps of C1 , C2 and C3 films. The values of the optical energy gaps of C1 , C2 and C3 are found to be 2.63 eV 2.09 eV and 3.24 eV, respectively. The data of both n and k in the absorption region were analyzed also to determine the real and imaginary parts of the complex dielectric constant, volume energy loss function and surface energy loss function as a function of the incident photon energy. For all compounds under test, the emission spectra has been investigating and it is found that the chromaticity diagram gave a green color emission.The AC dielectrical properties and AC conductivity (ac) were studied for three compounds C1 , C2 and C3 in bulk form (after compressed by a hydraulic press). The measurements were performed in the frequency range 100Hz – 5 MHz and in the temperature range 320 – 460 K. The temperature and frequency dependence of dielectric constants as well as ac were investigated. Real and imaginary parts of the dielectric constant for a fixed temperature were found to decrease with increasing frequency. Also, the Ac conduction mechanism is investigated. The Bulk Modulus of the three derivatives was also investigated.