TY  - JOUR
AU  - Sättele, Marie S.
AU  - Windischbacher, Andreas
AU  - Greulich, Katharina
AU  - Egger, Larissa
AU  - Haags, Anja
AU  - Kirschner, Hans
AU  - Ovsyannikov, Ruslan
AU  - Giangrisostomi, Erika
AU  - Gottwald, Alexander
AU  - Richter, Mathias
AU  - Soubatch, Serguei
AU  - Tautz, F. Stefan
AU  - Ramsey, Michael G.
AU  - Puschnig, Peter
AU  - Koller, Georg
AU  - Bettinger, Holger F.
AU  - Chassé, Thomas
AU  - Peisert, Heiko
TI  - Hexacene on Cu(110) and Ag(110): Influence of the Substrate on Molecular Orientation and Interfacial Charge Transfer
JO  - The journal of physical chemistry / C
VL  - 126
IS  - 10
SN  - 1932-7447
CY  - Washington, DC
PB  - Soc.
M1  - FZJ-2022-02096
SP  - 5036 - 5045
PY  - 2022
AB  - Hexacene, composed of six linearly fused benzene rings, is an organic semiconductor material with superior electronic properties. The fundamental understanding of the electronic and chemical properties is prerequisite to any possible application in devices. We investigate the orientation and interface properties of highly ordered hexacene monolayers on Ag(110) and Cu(110) with X-ray photoemission spectroscopy (XPS), photoemission orbital tomography (POT), X-ray absorption spectroscopy (XAS), low-energy electron diffraction (LEED), scanning tunneling microscopy (STM), and density functional theory (DFT). We find pronounced differences in the structural arrangement of the molecules and the electronic properties at the metal/organic interfaces for the two substrates. While on Cu(110) the molecules adsorb with their long molecular axis parallel to the high symmetry substrate direction, on Ag(110), hexacene adsorbs in an azimuthally slightly rotated geometry with respect to the metal rows of the substrate. In both cases, molecular planes are oriented parallel to the substrate. A pronounced charge transfer from both substrates to different molecular states affects the effective charge of different C atoms of the molecule. Through analysis of experimental and theoretical data, we found out that on Ag(110) the LUMO of the molecule is occupied through charge transfer from the metal, whereas on Cu(110) even the LUMO+1 receives a charge. Interface dipoles are determined to a large extent by the push-back effect, which are also found to differ significantly between 6A/Ag(110) and 6A/Cu(110).
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000776247200034
DO  - DOI:10.1021/acs.jpcc.2c00081
UR  - https://juser.fz-juelich.de/record/907590
ER  -