Accurate Energy Level Alignment at Physisorbed Molecule-Metal Interfaces from a Density Functional Theory-Based Approach
ORAL
Abstract
A highly relevant physical quantity for nanostructured molecule-metal interfaces is the energy level alignment of the molecular electronic states with respect to the Fermi level of the metal. Here, we introduce an efficient theoretical method that is based on density functional theory, but in contrast to common approximations fulfills physically motivated criteria for exchange-correlation interactions and can therefore yield quantitatively accurate energy level alignment information for physisorbed metal-molecule interfaces. We validate our approach by a detailed comparison with experimental and theoretical reference data for several prototypical interfaces of this kind: benzene on graphite (0001), and 1,4-benzenediamine, Cu-phthalocyanine, and 3,4,9,10-perylene-tetracarboxylic-dianhydride on Au(111). Our results indicate that obtaining quantitatively accurate energy level alignment information from density functional theory is possible.
–