TY  - EJOUR
AU  - Haags, Anja
AU  - Yang, Xiaosheng
AU  - Egger, Larissa
AU  - Brandstetter, Dominik
AU  - Kirschner, Hans
AU  - Gottwald, Alexander
AU  - Richter, Mathias
AU  - Koller, Georg
AU  - Ramsey, Michael G.
AU  - Bocquet, François C.
AU  - Soubatch, Serguei
AU  - Tautz, Frank Stefan
AU  - Puschnig, Peter
TI  - Benchmarking theoretical electronic structure methods with photoemission orbital tomography
PB  - arXiv
M1  - FZJ-2025-02313
PY  - 2022
AB  - In the past decade, photoemission orbital tomography (POT) has evolved into a powerful tool to investigate the electronic structure of organic molecules adsorbed on (metallic) surfaces. By measuring the angular distribution of photoelectrons as a function of binding energy and making use of the momentum-space signature of molecular orbitals, POT leads to an orbital-resolved picture of the electronic density of states at the organic/metal interface. In this combined experimental and theoretical work, we apply POT to the prototypical organic $π$-conjugated molecule bisanthene (C$_{28}$H$_{14}$) which forms a highly oriented monolayer on a Cu(110) surface. Experimentally, we identify an unprecedented number of 13 $π$ and 12 $σ$ orbitals of bisanthene and measure their respective binding energies and spectral lineshapes at the bisanthene/Cu(110) interface. Theoretically, we perform density functional calculations for this interface employing four widely used exchange-correlation functionals from the families of the generalized gradient approximations as well as global and range-separated hybrid functionals. By analyzing the electronic structure in terms of orbital-projected density of states, we arrive at a detailed orbital-by-orbital assessment of theory vs. experiment. This allows us to benchmark the performance of the investigated functionals with regards to their capability of accounting for the orbital energy alignment at organic/metal interfaces.
KW  - Materials Science (cond-mat.mtrl-sci) (Other)
KW  - Chemical Physics (physics.chem-ph) (Other)
KW  - FOS: Physical sciences (Other)
LB  - PUB:(DE-HGF)25
DO  - DOI:10.48550/ARXIV.2209.11516
UR  - https://juser.fz-juelich.de/record/1041556
ER  -