Calculating electronic and structural properties of self-assembled monolayers using density functional theory
Iris Hehn
14:40 - 15:20 Friday 26 June 2015 HS 05.12 Physikgebaeude, Universitätsplatz 5

Self-assembled monolayers (SAMs) offer the possibility to modify numerous different surface properties like chemical reactability, wetting behavior or electrical characteristics. Interfaces play a crucial role for the performance of various types of electrical devices. Including SAMs is a great way to tune the properties of such interfaces, offering a range of application possiblities for this field of research.
We are especially interested in modifying substrate work functions and creating specific potential distributions inside a SAM. To investigate these effects we study SAMs of mid-chain ester functionalized alkanethiols on gold substrates. What makes these molecules interesting is the large electric dipole moment situated in the middle of the carbon chain, which is not aligned parallel but at a certain angle to the molecular axis. This impacts the work function strongly and causes interesting side effects due to the unconventional position and alignment of the dipole moment. We study these systems on a quantum-mechanical level using density functional theory in combination with molecular dynamics simulations.