Presentation day

Tuesday  9:30 AM

 

TITLE

Computational approaches to investigating thio- and amino-based adsorbents on a gold surface -- a density functional theory (DFT) study

 

Abstract

Self assembled monolayers (SAMs) have a broad range of applications in nanotechnology
from sensor development to biomedical devices. Cysteine is the only proteinogenic amino acid containing a
thiol group, thus its behaviour on gold has repercussions on the adsorption properties of proteins and
peptides. Experimentally, scanning tunneling microscope (STM) images show that cysteine has a complex
phase behaviour when adsorbed on noble metal surfaces. In particular, this behaviour depends on a variety
of factors such as surface density, temperature and deposition rate.
In this study, we are focusing on things more fundamental than SAMs. We are interested in the binding of
the thio- and amino-groups on manually designed gold clusters, as well as their binding energies, sites, and
configurations. Calculations to determine binding sites are performed using density functional theory (DFT)
by varying between thio- and amino-adsorbents. We have investigated how binding structures and energies
depend on coordination at the adsorption sites on the gold cluster. The results of this study will be
discussed, including the relationship between the coordination number of gold and binding energies of
substrates adsorbed on the gold clusters. Additionally, analysis of the binding energies and conformations
when varying the adsorbent will be presented.