The theoretical studies of the intermediates generated from BrCH2CH2OH and ClCH2CH2OH on oxygen-precovered Cu (100)
| Autor: | Tao-Wei Fu, 傅道威 |
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| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 In this paper density-functional-theory calculations have been employed to investigate the vibrational frequencies, adsorption geometries and adsorption sites of the intermediates generated from BrCH2CH2OH and ClCH2CH2OH decomposition on oxygen-precovered Cu(100) surfaces in conjunction with the experimental studies of temperature-programmed reaction/desorption, reflection-absorption infrared spectroscopy. In the case of BrCH2CH2OH, -CH2CH2O- is the major intermediate at lower exposures(1.5L), BrCH2CH2O- is also generated. In the case of ClCH2CH2OH, ClCH2CH2O- is the reaction intermediate. DFT calculations predicted that the ClCH2CH2O- is most likely to be adsorbed at the four-fold hollow sites of Cu(100), with its C-O bond only slightly titled away from the surface normal and with a gauche conformation with respect to the C-C bond. The hollow-site ClCH2CH2O- has 4.4 and 19.2 kcal•mol-1 lower than the ClCH2CH2O- bonded at the bridging and atop sites, respectively. The effect of pre-covered oxygen on the ClCH2CH2O- bonding geometry and infrared band frequencies is not significant. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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