Theoretical study of ethynylbenzene adsorption on Au(111) and implications for a new class of self-assembled monolayer

M J Ford; R C Hoft; A McDonagh

doi:10.1021/jp053238o

Theoretical study of ethynylbenzene adsorption on Au(111) and implications for a new class of self-assembled monolayer

J Phys Chem B. 2005 Nov 3;109(43):20387-92. doi: 10.1021/jp053238o.

Authors

M J Ford¹, R C Hoft, A McDonagh

Affiliation

¹ Institute for Nanoscale Technology, University of Technology Sydney, P.O. Box 123, Broadway, NSW 2007, Australia. Mike.Ford@uts.edu.au

PMID: 16853638
DOI: 10.1021/jp053238o

Abstract

Density functional calculations of the adsorption of ethynylbenzene on the Au(111) surface show that, after cleavage of the C-H bond, the terminal carbon makes a strong covalent bond to the surface. The bond energy is shown to be about 70 kcal.mol(-1) with the fcc hollow site being most stable and the molecule oriented perpendicular to the surface. Adsorption without elimination of hydrogen is also possible via a hydrogen 1,2 shift to form a vinylidene surface-bound species, or opening of the C-C triple bond and adsorption through the two carbon atoms in a flat conformation. The reaction energy for formation of the surface-bound vinylidene is estimated to be 5 kcal.mol(-1) exothermic relative to the isolated ethynylbenzene and gold substrate.