Topological Stone–Wales Defects Enhance Bonding and Electronic Coupling at the Graphene/Metal Interface

B. P. Klein, A. Ihle, S. R. Kachel, L. Ruppenthal, S. J. Hall, L. Sattler, S. M. Weber, J. Herritsch, A. Jaegermann, D. Ebeling, R. J. Maurer, G. Hilt, R. Tonner-Zech, A. Schirmeisen, J. M. Gottfried, ACS Nano 16, 11979-11987 (2022)

"Defects in Graphene subtly affect the structural and electronic properties. We perform a detailed joint experiment/theory investigation of molecular precursors of pristine graphene and Stone-Wales defects in graphene to assess the structural and spectroscopic changes imposed by defects."

Topology Effects in Molecular Organic Electronics Materials: Pyrene and Azupyrene

Benedikt P. Klein, Lukas Ruppenthal, Samuel J. Hall, Lars E Sattler, Sebastian M. Weber, Jan Herritsch, Andrea Jaegermann, Reinhard J. Maurer, Gerhard Hilt, and Michael Gottfried, ChemPhysChem 22, 1-10 (2021)

"Using photoelectron spectroscopy, near edge X-ray absoption fine structure spectroscopy, and density functional theory, we characterize the electronic and optical properties of pyrene and azupyrene thin films. The differences between the properties of the two compounds can be understood in terms of their different bonding topology."

The Nuts and Bolts of Ab-Initio Core-Hole Simulations for K-shell X-Ray Photoemission and Absorption Spectra

B. Klein, S. J. Hall, R. J. Maurer, J. Phys. Condens. Matter 33, 154005 (2020)

"We present the numerical and technical details of our variants of the DeltaSCF and transition potential method (coined DeltaIP-TP) to simulate XPS and NEXAFS transitions. Using exemplary molecules in gas-phase, in bulk crystals, and at metal-organic interfaces, we systematically assess how practical simulation choices affect the stability and accuracy of simulations. We particularly focus on the choice of aperiodic or periodic description of systems and how spurious charge effects in periodic calculations affect the simulation outcomes. For the benefit of practitioners in the field, we discuss sensible default choices, limitations of the methods, and future prospects."