IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Semiconductors Thursday Sessions
       Session SC+SS+EL-ThM

Paper SC+SS+EL-ThM10
The Influence of Conjugation in Attachment of @pi@-Electron Containing Organic Molecules to the Si(001) Surface: Acrylonitrile vs. Allyl Cyanide

Thursday, November 1, 2001, 11:20 am, Room 111

Session: Interaction of Hydrogen and Organics with Silicon
Presenter: M.P. Schwartz, University of Wisconsin-Madison
Authors: M.P. Schwartz, University of Wisconsin-Madison
S.K. Coulter, University of Wisconsin-Madison
R.J. Hamers, University of Wisconsin-Madison
Correspondent: Click to Email
Organic chemists have developed methods for controlling chemical reactions of complex molecules by defining a broad and detailed set of rules for reactivity. Controlling electron density within a molecule through the use of electron donating or withdrawing groups is a very important way in which to influence product distributions. While a wide variety of unsaturated organic molecules can be tethered to the Si(001) surface, little is known about the role of conjugation of @pi@-electrons in influencing product distribution. In this study, we have investigated the attachment of acrylonitrile (CH2=CH-CN) and allyl cyanide (CH2=CH-CH2-CN) to the Si(001) surface to determine how conjugation of an electron withdrawing group to a vinyl group influences the final surface products. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) measurements show that the attachment chemistry differs significantly for these two molecules. Allyl cyanide adsorbs primarily through the vinyl group while acrylonitrile attaches predominantly via the cyano group. Acetonitrile and benzonitrile were also studied to help determine the nature of the final surface products. The role of conjugation in determining product distributions for attachment of allyl cyanide and acrylonitrile to the Si(001) surface will be discussed.