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Nuzzo, Ralph G. Street, Shane Clark 2011-05-07T12:24:05Z 2011-05-07T12:24:05Z 10000-01-01 1995 Surface analytical techniques have been used to study the interaction of straight-chain alcohols with a preoxidized single-crystal Cu(111) surface under ultra-high vacuum conditions. The adsorbed alcohols deprotonate to form stable alkoxides chemisorbed to the surface. These alkoxides decompose at elevated temperatures by $\beta$-hydride elimination, desorbing as aldehydes. The influence of deuterium isotope labelling, selective fluorination, and chain length on this mechanism has been studied. Temperature Programmed Reaction (TPR) spectra for the reactions of ethoxides and 1-propoxides and their selectively deuterated counterparts reveal both primary kinetic isotope effects and measurable secondary isotope effects. Fourier Transform Infrared Reflection Absorption Spectra (FT-IRAS) have been obtained for ethoxide, selectively fluorinated and deuterated ethoxides, 1-propoxide and selectively deuterated 1-propoxides, at saturation coverages on the Cu(111) surface. Quantitative measurements of the absorption intensities of the absorbed alkoxides and the randomly oriented corresponding alcohols allowed determination of the orientation of the adsorbed ethoxide and trifluoroethoxide. Ethoxide on the Cu(111) surface has the C-C bond tilted 70 $\pm$ 2$\sp\circ$ from the surface normal while in trifluoroethoxide the C-C bond is oriented 50 $\pm$ 5$\sp\circ$ from the surface normal. In both species the plane of the molecule defined by the C-C-O atoms is tilted towards the surface. This tilt between the plane of the molecule and the plane of the surface normal is 17 $\pm$ 2$\sp\circ$ for ethoxide and 20 $\pm$ 11$\sp\circ$ for trifluoroethoxide. The FT-IRAS spectra of the 1-propoxides have been compared to the reflection infrared spectra of self-assembled monolayers containing long alkyl chains. The spectra show evidence for both crystalline-like packing and conformational disorder in the adlayer, suggesting the presence of both ordered and disordered domains of the alkoxides on the Cu(111) surface. Finally, the FT-IRAS spectra of propene and a set of fluorinated propenes have been obtained. These physisorbed molecules are shown to lie with their molecular C-C=C planes parallel to the metal surface. Made available in DSpace on 2011-05-07T12:24:05Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9624503.pdf: 6276979 bytes, checksum: f097f66c2f5de6e3558b9a1222d8820f (MD5) Previous issue date: 1995 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:40:34Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:17:25-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission ETDs are only available to UIUC Users without author permission U of I Only AAI9624503 (UMI)AAI9624503 http://hdl.handle.net/2142/19955 eng Copyright 1995 Street, Shane Clark Chemistry, Physical Orientation and chemistry of alkoxides on copper(111) text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.