Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 5: Nanostructures at Surfaces I: Organics

O 5.10: Vortrag

Montag, 1. April 2019, 12:45–13:00, H15

Probing the Potential Landscape of Rotating Co(II)-5,15-diphenylporphyrin on CoO (111) Films — •Feifei Xiang and M. Alexander Schneider — Solid State Physics, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany

The adsorption of Co(II)-5,15-diphenylporphyrin (Co-DPP) on CoO (111) films of different thicknesses grown epitaxially on Ir (100) is studied by low-temperature scanning tunneling microscopy (STM) operated at 77 K. Unlike non-metalated DPP (2H-DPP), Co-DPP is observed to rotate around its metal center on CoO (111) films exceeding 1BL thickness at 77 K. By lateral manipulation, the rotation can be switched 'on' and 'off' by moving the rotating molecule to adjacent molecules. The rotating molecule appears in STM as a height modulated round feature, the modulation is attributed to the lifetime of a certain molecular orientation and reflects the local potential landscape.[1] We observe that the modulation patterns of Co-DPP vary with CoO film thickness from 2BL to 11BL. Especially the appearance of a 90° degeneracy of the potential landscape is unexpected in view of the hexagonal surface symmetry of films thicker than 2BL.

Reference

[1] Gao, L.; et al. Phys. Rev. Lett. 2008, 101 (19), 197209.