Spectroelectrochemical investigations of pyrimidine-2-thionato-bridged binuclear platinum(III) complexes

Ozbek, Ozge
Özkan, İlker
Önal, Ahmet Muhtar
The electrochemical behavior of the binuclear platinum(III-III) complexes [Pt-2(C4H3N2S)(4)X-2] (C4H3N2S- = pyrimidine-2-thionate; X- = Cl--,Cl- Br--,Br- I-) have been studied by cyclic voltammetry and insitu spectroelectrochemistry in an acetonitrile-tetrabutylammonium tetrafluoroborate solventelectrolyte couple. An irreversible metal based reduction appears during the cathodic scan for each of the three complexes. The changes in UV-Vis spectra observed in-situ during the reductive electrolysis indicate that all three complexes give the same product, [Pt-2(C4H3N2S)(4)], with a Pt(II)-Pt(II) system. The changes in the reduction potentials of the complexes on changing the axial ligands are interpreted by the changes in the energy of the LUMO level, which is determined by the degree of sigma- and it-interactions of the axial halide ligands with the metal atoms. DFT (B3LYP/LanL2DZ) calculations support our experimental data.


Spectroelectrochemical Investigation of Nuclease Active Pt(II) Complexes Containing Pyrrole Oxime
Altunöz Erdoğan, Deniz; Kayi, Hakan; Ozalp-Yaman, Seniz (2015-03-10)
In this paper, the electrochemical oxidation of three Pt(II) complexes containing pyrrole oxime (HL) having a general formula of [Pt(NH3)Cl(L)] (1), [Pt(L)(2)] (2), and K[PtCl2(L)] (3) has been investigated by in-situ spectroelectrochemistry in dimethylformamide (DMF). An irreversible metal-based oxidation process occurs during the anodic scan for each of the three complexes. The electronic absorption spectral changes indicate that all the three complexes generate similar Pt(IV) compounds and free ligand. O...
Spectroelectrochemical investigation of pentacarbonyl(pyrazine)metal(0) (metal = Cr, Mo, W) complexes of group 6 elements
Yaman, SO; Nalbant Esentürk, Emren; Kayran, C; Önal, Ahmet Muhtar (2002-01-01)
The electrochemical behaviour of pentacarbony l(pyrazine) metal (0) complexes of the group 6 elements was studied by cyclic voltammetry in dichloromethane-(n-Bu)(4)NBF4 solvent-electrolyte couple at -20 degreesC vs. Ag/Ag+ or SCE reference electrode. Constant potential electrolyses of the complexes were carried out at their first oxidation peak potentials and monitored in situ by UV-Vis spectrometry. Electrolysis of W(CO)(5)pz produces [W(CO)(5)pz](+) and a similar electrochemical mechanism is expected both...
Terahertz spectroscopy of dicyanobenzenes: Anomalous absorption intensities and spectral calculations
Esentürk, Okan; Heilweil, E. J. (2007-07-06)
Terahertz absorption spectra of three isomeric structures of dicyanobenzene in chloroform solution and solid phase at 298 K are reported. These spectra exhibit enhanced absorption in low THz range compared to most organic systems because of strong coupling to phonon modes. Molecular vibrational spectral calculations show strong correlation with the experiment especially for solution spectra. All intramolecular modes were assigned and intermolecular modes identified. Out-of-plane intramolecular modes at low ...
Spectroscopic modification of the Pippard relation applied for the translational mode in ammonia solid II near the melting point
Yurtseven, Hasan Hamit; Yıldız, İlker (Elsevier BV, 2005-09-01)
This study gives our calculation for the frequency shifts 1/V(partial derivative v/partial derivative T)(P) and the specific heat C-p near the melting point in the ammonia solid II. We establish a linear relationship between C-p and 1/v(partial derivative v/partial derivative T)(P) using the Raman frequencies of the translational mode which we calculated in this system. This leads to the validity of the spectroscopic modification of the first Pippard relation in the ammonia solid II near the melting point. ...
Epoxidation of Propylene on a [Ag14O9] Cluster Representing Ag2O (001) Surface: A Density Functional Theory Study
Fellah, Mehmet Ferdi; Önal, Işık (2012-01-01)
Density functional theory calculations were employed to study partial oxidation of propylene on a [Ag14O9] cluster representing Ag2O (001) surface for which positive effect for ethylene oxide formation has been reported in our earlier work at the same level of theory (Fellah et al., Catal Lett 141: 762, 2011). Propylene oxide (PO), propanal, acetone and G-allyl radical formation reaction mechanisms were investigated. P-allyl formation path and two propylene adsorption paths resulting in PO formation are com...
Citation Formats
O. Ozbek, Ş. ÖZALP YAMAN, İ. Özkan, A. M. Önal, and H. İŞÇİ, “Spectroelectrochemical investigations of pyrimidine-2-thionato-bridged binuclear platinum(III) complexes,” POLYHEDRON, pp. 122–128, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32598.