Project A3: Organic Heterolayer Systems: Structure and Vibrational Excitations
Principle Investigator: Prof. Dr. Peter Jakob (Marburg, Dept. of Physics)
Summary
This
project focuses on a detailed microscopic understanding of buried
interfaces between organic thin films and metal substrates (via a
molecular contact layer), as well as at the boundary of organic
heterolayer systems. Thereby, infrared absorption spectroscopy (IRAS)
will be used to investigate specific vibrational excitations at the
organic/organic and organic/inorganic boundaries, for example,
interfacial dynamical charge transfer associated with vibrational
excitations. A major effort will be devoted to the in-situ preparation
and characterization of customized layers. We will look into the
structure and thermal stability of the interfaces with bare and
functionalized metal surfaces and analyze related processes.
Specifically, interfaces of organic heterolayer systems will be
examined in terms of thin film inner structure, interdiffusion of the
layered compounds, covalent bond formation and orientation effects at
the interface.
On the basis of our excellent analytical characterization methods and
control of growth conditions, sophisticated recipes to grow layered
structures far from equilibrium will be developed. These in particular
comprise increasingly more complex architectures as well as δ-layers
embedded within homogeneous organic thin films. A major challenge of
IRAS is to identify and characterize vibrational modes associated with
the discontinuity at the interface, i.e. (i) modified bulk modes and
(ii) genuine interface modes associated with species (atoms, molecules)
exclusively located at the interface, or, specific binding
configurations thereof. In this respect one of our aims is to identify
chemical reactions at the interface by means of detection of specific
low frequency vibrational modes.
Project-Related Publications
- S. Thussing, P. Jakob
Thermal Stability and Interlayer Exchange Processes in Heterolayers of CuPc and PTCDA on Ag(111)
J. Phys. Chem. C 121, 13680 (2017). - S. Thussing, L. Fernández, P. Jakob
Thermal stability and interlayer exchange processes in heterolayers of TiOPc and PTCDA on Ag(111)
J. Phys.: Condens. Matter 31, 134002 (2019) - Special Issue on Internal Interfaces. - S. Thussing, S. Flade, K. Eimre, C.A. Pignedoli, R. Fasel, P.
Jakob
Reaction Pathway toward Seven-Atom-Wide Armchair Graphene Nanoribbon Formation and Identification of Intermediate species on Au(111)
J. Phys. Chem. C 124, 16009 (2020). - P. Jakob*, S. Thussing
Vibrational Frequency used as Internal Clock Reference to access Molecule - Metal Charge Transfer Times
Phys. Rev. Lett. (2020) - under review.