Quantum mechanical calculation of nitrous oxide decomposition on transition metals

Download

index.pdf

Date

2007

Author

Karaöz, Muzaffer Kaan

Metadata

Show full item record

Item Usage Stats

229
views

59
downloads

Nitrous oxide decomposition on Ag51, Au51, Pt22, Rh51 and Ir51 clusters representing (111) surface were studied quantum mechanically by using the method of ONIOM with high layer DFT region and low layer of molecular mechanics region utilizing universal force field (UFF). The basis set employed in the DFT calculations is the Los Alamos LANL2DZ effective core pseudo-potentials (ECP) for silver, gold, platinum, rhodium and iridium and 3-21G** for nitrogen, oxygen and hydrogen. Nitrous oxide was decomposed on the all metal surfaces investigated in this study by leaving oxygen atom adsorbed as supported by experimental findings. Activation energies of nitrous oxide decomposition on Ag51, Au51, Pt22, Rh51 and Ir51 representing (111) surface are calculated as 14.48 kcal/mol, 15.72 kcal/mol, 7.02 kcal/mol, 3.76 kcal/mol and 5.51 kcal/mol, respectively. Based on these results, decomposition of nitrous oxide occurs on Rh more easily than other metals.

Subject Keywords

Quantum chemistry.

URI

http://etd.lib.metu.edu.tr/upload/12608999/index.pdf
https://hdl.handle.net/11511/17297

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Quantum-chemical treatment of the linoleic acid molecule and two of its conjugated isomers Kurban, Sevil; ERKOÇ, Figen; Erkoç, Şakir (Wiley, 2009-10-01) The structural, vibrational and electronic properties of die linoleic acid molecule and two of its conjugated isomers were investigated theoretically by performing the molecular mechanics (MM+ force field), the semi-empirical self-consistent-field molecular-orbital (PM3), and the density functional theory (B3LYP) calculations. The geometries of the considered molecules were optimized; the vibrational dynamics and the electronic properties were calculated in their ground states in the gas phase. It was found...
Quantum chemical investigation of thalidomide molecule Erkoç, Şakir; Erkoc, F (Elsevier BV, 2005-04-14) The structural and electronic properties of the thalidomide molecule have been investigated theoretically by performing semi-empirical molecular orbital (AM1) and density functional theory calculations. The geometry of the molecule has been optimized by AM1 method and the electronic properties of the molecule have been calculated by density functional theory in its ground state.
In situ DRIFTS characterization of wet-impregnated and sol-gel Pd/TiO 2 for NO reduction with CH4 Karakaş, Gürkan; Ozkan, Umit S. (Elsevier BV, 2002-05-01) The adsorption/desorption behavior of 2%Pd/TiO2 catalysts synthesized by wet-impregnation and modified sol–gel techniques were examined in NO–CH4–O2 reaction using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The catalyst prepared by the modified sol–gel method showed significantly higher resistance toward oxygen while maintaining a 100% NO conversion. Under NO+CH4+O2 flow, the main adsorbed NO species was identified as the linearly adsorbed NO on metallic palladium (Pd0–NO)...
Phase transition of chemically synthesized FePt nanoparticles under high pressure ŞİMŞEK, TELEM; Karci, Ozgur; ÖZCAN, ŞADAN (The Scientific and Technological Research Council of Turkey, 2018-01-01) We present the results of a study related to phase transformation of chemically synthesized FePt nanoparticles under high pressure from face-centered cubic into face-centered tetragonal structure. As-synthesized nanoparticles are around 4.5 nm and show superparamagnetic behavior at 300 K. After annealing under 60 bar pressure of hydrogen at 400 degrees C for 2 h, nanoparticles exhibit strong ferromagnetic behavior with 5391 Oe coercivity. Results show that high-pressure annealing lowers the decomposition te...
Voltammetric methods of reboxetine analysis and the mechanism of its electrode reactions Altunöz Erdoğan, Deniz; Erk, Nevin; Kilic, Esma (Walter de Gruyter GmbH, 2013-05-01) Reboxetine (RBX) electrochemical redox behavior at hanging mercury drop (HMDE) and glassy carbon electrodes (GCE) was studied in various pH Britton-Robinson universal buffers using cyclic voltammetry and square-wave voltammetry. RBX was reduced at the HMDE and oxidized at the GCE with reversible adsorption controlled and irreversible diffusion controlled processes respectively. The anodic peak is due to the amine and the cathodic peak may correspond to oxygen protonation. An oxidation reaction mechanism is ...

Citation Formats

M. K. Karaöz, “Quantum mechanical calculation of nitrous oxide decomposition on transition metals,” M.S. - Master of Science, Middle East Technical University, 2007.