Binding and electronic level alignment of π-conjugated systems on metals
Abstract
We review the binding and energy level alignment of π-conjugated systems on metals, a field which during the last two decades has seen tremendous progress both in terms of experimental characterization as well as in the depth of theoretical understanding. Precise measurements of vertical adsorption distances and the electronic structure together with ab initio calculations have shown that most of the molecular systems have to be considered as intermediate cases between weak physisorption and strong chemisorption. In this regime, the subtle interplay of different effects such as covalent bonding, charge transfer, electrostatic and van der Waals interactions yields a complex situation with different adsorption mechanisms. In order to establish a better understanding of the binding and the electronic level alignment of π-conjugated molecules on metals, we provide an up-to-date overview of the literature, explain the fundamental concepts as well as the experimental techniques and discuss typical case studies. Thereby, we relate the geometric with the electronic structure in a consistent picture and cover the entire range from weak to strong coupling.
- Publication:
-
Reports on Progress in Physics
- Pub Date:
- June 2020
- DOI:
- 10.1088/1361-6633/ab7a42
- arXiv:
- arXiv:2002.10455
- Bibcode:
- 2020RPPh...83f6501F
- Keywords:
-
- π-conjugated molecules on metals;
- vertical adsorption distances;
- energy-level alignment;
- x-ray standing waves;
- photoelectron spectroscopy;
- Condensed Matter - Materials Science
- E-Print:
- 50 pages, 28 figures, 2 tables peer-reviewed version, accepted by Reports on Progress in Physics