Regensburg 2010 – wissenschaftliches Programm
O 6.4: Vortrag
Montag, 22. März 2010, 12:00–12:15, H36
STM/STS study of Spiro-DPO molecules on Au(111) — •Michael H. Waelsch1, Tatjana Podlich1, Melanie Klinke1, Tobat P. I. Saragi2, Josef Salbeck2, and René Matzdorf1 — 1Universität Kassel, Experimentalphysik II, — 2Universität Kassel, AG Makromolekulare Chemie und Molekulare Materialien, FB 18 Naturwissenschaften, Heinrich-Plett-Str. 40, 34132 Kassel
In the Spiro-DPO molecule an electron transport material (donor) is linked to a hole transport material (acceptor) via a Spiro-C-atom.
The arrangement of about 1/10 ML Spiro-DPO on a Au(111)-substrate has been investigated with respect to the molecular energy-levels by STM/STS in UHV at 4.8 K. We observed amorphous clusters of molecules, which showed obvious shifts in their HOMO- and LUMO-energies, if the sample was annealed above the glass transition temperature. The shifts may be due to screening by the surrounding molecules. Without annealing the molecules arrange in rings, double rows and chains, depending on the underlying Au(111)-herringbone-reconstruction. In these structures the HOMO/LUMO-levels measured with STS are less shifted than in the amorphous clusters.