Abstract:
Gold is widely used in nanotechnology, for example as a substrate in forming self-assembled
monolayers or as nanoparticles for their unique optical and chemical properties. In this paper we
give an overview of the properties of gold relevant to its potential application in molecular-scale
devices and present some of our recent computational predictions. Density functional calculations
of molecular adsorption onto gold surfaces were used to investigate the effect of surface symmetry
and identify new linking schemes for self-assembled monolayers. Adsorption energies of
methylthiolate (SCH3) onto the (111), (100) and (110) surfaces of gold are predicted to be 39.3,
48.4 and 51.1 kcal/mol respectively and demonstrate that selective functionalisation of the surfaces
is possible. Phosphine molecules with at least two hydrogen atoms substituted for methyl groups
are predicted to form Au-P surface bonds with energies of about 13-20 kcal/mol.
