Çırak, Çaǧrı; Körözlü, Nurettin; Sert, Yusuf; Ucun, Fatih

The ground state hydrogen conformations and vibrational analysis of 3-deazauracil (3DAU) and 6-azauracil (6AU) tautomers (4-enol and 2,4-diol forms) have been calculated using ab initio Hartree-Fock (HF) and density functional theory (B3LYP) methods with 6-311++G(d,p) basis set level. The calculations have shown that the most probably preferential tautomer of 3DAU and 6AU are the 4-enol form, which gives best fit to the corresponding experimental data. The ground state conformer of the 2,4-diol form has two O-H bonds which are oriented externally and internally (to the N-H bond). The vibrational analyses of the ground state conformer of each tautomeric form of 3DAU and 6AU were done and their optimized geometry parameters (bond lengths and bond angles) were given. Furthermore, from the correlations values it was concluded that the B3LYP method is superior to the HF method for both the vibrational frequencies and the geometric parameters.

Morkoç Karadeniz, S.; Tatar, Demet; Ertuğrul, M.; Ekinci, A.E.

In this study, Tungsten Oxide (WO3) thin films were prepared by Chemical Spray Pyrolysis (CSP) and Spin Coating (SC) techniques and it was investigated effects of technique and parameter on the films. WO3 thin films were deposited on ITO (Indium Tin Oxide) coated glasses. The structural, optical and electrochromic properties of the WO3 thin films were characterized by XRD, SEM, UV, and CV measurements. The sharpest (200) peak was observed in the XRD spectra and optical band gaps were calculated around 2.6~3.1 eV via UV-Vis spectra for all of the samples. Micro fibrous reticulated surface (filamentous like) morphology for the films deposited by CSP technique and smooth surface morphology with high optical transmittance for the film deposited by SC Technique were obtained from SEM images. In addition to these results, it was revealed that all the samples exhibit good electrochromic performance.

Oturak, Halil; Kinaytürk, Neslihan Kaya; Cirak, Cagri

In the present work, the experimental and the theoretical spectroscopic properties of 1-Methyl-6-Nitro-1H- Benzimidazole were investigated. The FT-IR (400~4 000 cm-1) and FT-Raman spectra (100~4 000 cm-1) of 1-Methyl-6-Nitro-1H- Benzimidazole in the solid phase were recorded. Also, experimental NMR and UV spectra of titled molecule were measured. To interpret the experimental data, geometric parameters, vibrational frequencies, NMR, UV spectra and NLO analysis of the optimized molecule were calculated using ab initio Hartree-Fock (HF) method and density functional theory (B3LYP) method with the 6-31++G(d,p) and 6-311++G(d,p) basis sets. Vibrational bands were assigned based on the potential energy distribution using the VEDA 4 program. The theoretical results showed good agreement with the experimental values.

Durdaği, Sevil(Porikli)

Spectra of K X-rays emitted from pure 3d transition metals and their oxide and sulfate compounds were measured using a single crystal wavelength dispersive X-ray spectroscopy (WDXRF). The measurements were performed using a ZSX-100e sequential spectrometer equipped with an Rh X-ray tube operated. An accurate analytical representation of each line was obtained by a fit to a Lorentz function. The spectra were analyzed in order to examine the K X-ray peak parameters such as asymmetry index, peak energy and relative intensity ratios. The energy shifts and relative intensities weredetermined tobetter understand the chemical effect.

Karadeniz, Sibel Morkoç; Kılınç, Tuba; Çırak, Burcu Bozkurt; Sakaoğlu, Tuba Irmak; Çırak, Çağrı; Ertuğrul, Mehmet; Ekinci, Ali Ercan

In this Study, Cadmium Oxide (CdO) nanostructures were synthesized by using Chemical Bath Deposition Technique. The synthesized process was carried out at room temperature. The structural and optical properties of nanostructures was characterized by XRD, SEM and UV-Vis techniques. As a result, the CdO nanostructures are oriented along (111) plane of cubic crystal structure. The morphology of CdO nanostructures showed interconnected prism-like and cauliflower-type cluster nanostructure. The UV results of this structures with high absorbtion coefficient are observed to be in accordance with the CdO nanoparticles.