Abstract
In this work we investigate the formation of crystalline organic thin films for p-sexiphenyl (6P) on Ag(001) with a combination of STM, LEED, TPD, SFM, UPS, XRD and DFT. For weakly interacting van-der-Waals-dominated systems of small organic molecules on single crystalline metals we demonstrate the complex epitaxial evolution from sub-monolayer to bulk structure. In the delicate interplay between molecule-substrate and intermolecular interactions we identify the oligo-phenyl's flexibility of central importance for the film growth. We observe a change from a planar to a twisted molecular conformation and, accompanying, a molecular realignment during the formation of a dense monolayer as the result of enhanced 2-dimensional intermolecular interaction. A second molecular realignment occurs collectively for whole domains with the formation of 3-dimensional bilayer structures. Finally the bilayer acts as a template for the epitaxial growth of the molecular thin film, determining the azimuthal orientation and a single contact plane for the organic crystallites.
Original language | English |
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Pages (from-to) | 149-156 |
Number of pages | 8 |
Journal | Surface Science |
Volume | 678 |
DOIs | |
Publication status | Published - 1 Dec 2018 |
Keywords
- Bilayer
- Molecular conformation
- Organic thin film
- Realignment
- Reorientation
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry