IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Surface Science Tuesday Sessions
       Session SS+BI-TuM

Paper SS+BI-TuM5
Characterization of Self-assembled Monolayers Using Near-edge X-ray Absorption Spectroscopy

Tuesday, October 30, 2001, 9:40 am, Room 120

Session: Poirier Memorial Session: Self-Assembled Monolayers I
Presenter: T.M. Willey, Univ. of California at Davis and Lawrence Livermore National Lab
Authors: T.M. Willey, Univ. of California at Davis and Lawrence Livermore National Lab
A.L. Vance, Lawrence Livermore National Lab
A.W. vanBuuren, Lawrence Livermore National Lab
C.F.O. Bostedt, Univ. of Hamburg, Germany, and Lawrence Livermore National Lab
G.A. Fox, Lawrence Livermore National Lab
A.J. Nelson, Lawrence Livermore National Lab
L.J. Terminello, Lawrence Livermore National Lab
C.S. Fadley, Unive. of California at Davis and Lawrence Berkeley National Lab
Correspondent: Click to Email
We have investigated methyl and carboxyl terminated alkanethiols (hexadecanethiol and mercaptohexadecanoic acid) and other more complex self-assembled monolayers (SAMs) on Au(111). We characterize these SAMs using x-ray absorption at the Carbon K-edge, Sulfur L-edge, ans well as Oxygen and Nitrogen K-edges where applicable. Near-edge X-ray Absorption Spectroscopy (NEXAFS) gives information about chemical state, and polarization effects in these spectra probe the orientation of chemical bonds. Simple, carboxyl-terminated alkanethiols supposedly do not form well-ordered films. We currently investigate attachment, uniformity, and order of these films as a function of solvent, chemical state of the carboxyl group, and by intermixing with well-ordering methyl-terminated alkanethiols. We have also investigated attachment and order of more complex, disulfide containing thioctic acid derivatives. Preliminary results indicate that we have been successful in chemisorbing both sulfur-functionalized ends of a number of these molecules to the gold surface. T. Willey acknowledges a Student-Employee Graduate Research Fellowship through LLNL. This work is supported by the U.S. Department of Energy, BES Materials Sciences under contract W-7405-ENG-48, LLNL.