Thioglycolic acid on the gold (111) surface and Raman vibrational spectra

Jian-Ge Zhou; Quinton L Williams; Ruqian Wu

doi:10.1063/1.3319711

Thioglycolic acid on the gold (111) surface and Raman vibrational spectra

J Chem Phys. 2010 Feb 14;132(6):064702. doi: 10.1063/1.3319711.

Authors

Jian-Ge Zhou¹, Quinton L Williams, Ruqian Wu

Affiliation

¹ Department of Physics, Atmospheric Sciences, and Geoscience, Jackson State University, Jackson, Mississippi 39217, USA. jiange.zhou@jsums.edu

PMID: 20151751
DOI: 10.1063/1.3319711

Abstract

The interaction of thioglycolic acid (HSCH(2)COOH) with the Au(111) surface is investigated, and it is found that at the low coverage the molecule lies down on the substrate. If the mercaptan-hydrogen atom is eliminated, the resulting SCH(2)COOH molecule is randomly oriented on the surface. If the carboxylic acid group in the HSCH(2)COOH molecule is deprotonated instead, the HSCH(2)COO(-) molecule lies down on the surface. However, when the mercaptan-hydrogen atom in the HSCH(2)COO(-) molecule is removed, the resulting SCH(2)COO(-) molecule rises up to a certain level on the substrate. The calculated Raman vibrational spectra decipher which compounds and atomic displacements contribute to the corresponding frequencies. We thus propose a consistent mechanism for the deposition of thioglycolic acid on the Au(111) surface.