Taner Arslan

Inhibition Effects of Amides on the Corrosion of Copper in 1.0 M HCl: Theoretical and Experimental Studies

Abstract The corrosion inhibition effects of benzamide (BA) and 4-aminobenzenesulfonamide (ABSA) for copper in 1.0 M hydrochloric acid (HCl) solution were investigated using potentiodynamic polarization, cyclic voltammetry (CV), and potentiostatic current-time curves. The Langmuir adsorption isotherms of the inhibitors were used to explain the adsorption behavior. In addition, surface analysis of copper was investigated using scanning electron microscopy (SEM). The results showed that the inhibition efficiency of ABSA was much better than those of BA. The theoretical study on the corrosion inhibition efficiencies for neutral and protonated forms of the BA and ABSA molecules were performed using density functional theory (DFT) and MP2 method in gas and water phases.

A theoretical study on the molecular structure and vibrational (FT-IR and Raman) spectra of cyano-bridged heteronuclear polymeric complex of triethylenetetramine

The cyano bridged complex of triethylenetetramine was characterized by FT-IR, Raman spectroscopy and X-ray single crystal diffraction analysis. The molecular geometry and vibrational frequencies of the complex in the ground state have been calculated by using B3LYP density functional method with LANL2DZ basis set. A good correlation was found via comparison of the experimental and theoretical vibrational frequencies of complex. The complex of the type [Zn(teta)Ni(μ-CN)(2)(CN)(2)](n) has been studied in the 4000-250cm(-1) region and assignment of all the observed bands were made. The analysis of the FT-IR and Raman spectra indicates that there are some structure spectra correlations.

Interactions of trivalent lanthanide cations with a hexadentate Schiff base derived from the condensation of ethylenediamine with 8-hydroxyquinoline-2-carboxaldehyde

Lanthanide(III) complexes [Ln(NO3)2(HL)] where Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb and Lu and LH2 = N,N′-bis(quinolin-8-ol-2-ylmethylidene)ethane-1,2-diamine, have been obtained by direct reaction of the di-Schiff base ligand and the corresponding hydrated lanthanide(III) nitrates in methanol/DMF solvent systems. All complexes were characterized with microanalyses, spectroscopically (IR and electronic spectra) and thermogravimetrically. Theoretical studies have also been undertaken to estimate possible structures. All the data are discussed in terms of the nature of the bonding and the possible structural types. All complexes appear to be monomeric with the organic ligand being singly deprotonated and behaving as a hexadentate chelating ligand.

Theoretical studies on the molecular structure and vibrational spectra of some dimethyl substituted pyridine derivatives.

AbstractThe molecular geometries, normal mode frequencies, intensities and corresponding infrared assignments of monomeric and dimeric 2,3-dimethylpyridine, 2,4-dimethylpyridine, 3,4-dimethylpyridine, 3,5-dimethylpyridine and monomeric 2,6-dimethylpyridine in the ground state were investigated at the density functional theory (DFT)-B3LYP level using the 6-311+G(d, p) basis set. The vibrational frequencies and geometric parameters of C–H stretching and bending in the fundamental region were calculated and compared to the Fourier transform infrared (FT-IR) data obtained. In the studied monomeric and dimeric dimethyl substituted pyridine derivatives, the C–H stretching and bending frequency shifts that occur between the dimer and the monomer may be diagnostic of the magnitude of dimerization energy. As supported by data in the literature, the most stable dimeric form was obtained for the 3,4-dimethylpyridine molecule. FigureMolecular model and numbering scheme of the studied dimeric dimethylpyridinederivatives

Inhibition Effects of 4-Phenyl-3-Thiosemicarbazide on the Corrosion of Aluminum in 0.1 M HCl: Theoretical and Experimental Studies

Abstract The inhibition effects of 4-phenyl-3-thiosemicarbazide (PT) on the corrosion of aluminum in 0.1 M hydrochloride acid (HCl) solution at 298 K to 343 K using potentiodynamic polarization hav...

ETM-ANN Approach Application for Thiobenzamide and Quinolizidine Derivatives

The structure anti-influenza activity relationships of thiobenzamide and quinolizidine derivatives, being influenza fusion inhibitors, have been investigated using the electronic-topological method (ETM) and artificial neural network (ANN) method. Molecular fragments specific for active compounds and breaks of activity were calculated for influenza fusion inhibitors by applying the ETM. QSAR descriptors such as molecular weight, EHOMO, ELUMO, ΔE, chemical potential, softness, electrophilicity index, dipole moment, and so forth were calculated, and it was found to give good statistical qualities (classified correctly 92%, or 48 compounds from 52 in training set, and 69% or 9 compounds from 13 in the external test set). By using multiple linear regression, several QSAR models were performed with the help of calculated descriptors and the compounds activity data. Among the obtained QSAR models, statistically the most significant one is the one of skeleton 1 with R2 = 0.999.

New Heterocyclic Phosphorus Ylides: Synthesis, Crystal Structure, and Theoretical Calculation of Alkyl Substituted 3-(4-Benzoyl-1,5-diphenyl-2,3-dihydro-1H-pyrazol-3-yl)-3-oxo-2-(triphenylphosphoranylidene) Propanoates

Novel alkyl substituted 3-(4-benzoyl-1,5-diphenyl-2,3-dihydro-1H-pyrazol-3-yl)-3-oxo-2-(triphenylphosphoranylidene) propanoates (3) were synthesized from 4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonylchloride (1) and alkyl (triphenylphosphoranylidene) acetates (2a–b). The synthesized compounds were characterized by elemental analysis, spectroscopic studies (3a–b), and single crystal X-ray diffraction (3a). The mechanism of the reaction between (1) and (2a) was studied by AM1, and the geometrical parameters of the studied molecules were also carried out in B3LYP methods with the standard 6–31G (d,p) basis set. NBO analysis were studied for 1 and 2a B3LYP methods with the standard 6–31G (d,p) basis set.

Quantum Chemical Calculations for some Isatin Thiosemicarbazones

Derivatives of isatin are reported to be present in mammalian tissues and body fluids (Casas et al., 1996; Agrawal & Sartorelli, 1978; Casas et al., 1994; Medvedev et al., 1998; Boon, 1997; Pandeya & Dimmock, 1993; Rodriguez-Arguelles et al., 1999; Casas et al., 2000) and possess antibacterial (Daisley & Shah, 1984), antifungal (Piscopo et al., 1987), and anti-HIV (Pandeya et al., 1998, 1999) activities. N-methylisatin--4’, 4’ – diethylthiosemicarbazone were also reported to have activity against the viruses such as cytomegalo and moloney leukemia viruses (Sherman et al., 1980; Ronen et al., 1987). With the help of combinatorial method, the cytotoxicity and antiviral activities of isaitin--thiosemicarbazones against the vaccine virus and cowpox virus-infected human cells were evaluated (Pirrung et al., 2005).