The epitaxial sexiphenyl (0 0 1) monolayer on TiO2(1 1 0): A grazing incidence X-ray diffraction study |
| |
Authors: | R Resel M Oehzelt O Lengyel TU Schülli G Hlawacek C Teichert G Koller |
| |
Institution: | a Institute of Solid State Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria b CEA Grenoble, DRFMC/SP2M/NRS, 17 avenue des Martyrs, 38054 Grenoble, France c Institute Charles Sadron, CNRS-UPR 22, 6, rue Boussingault, Strasbourg, France d Institute of Physics, University Leoben, Franz Josef Straße 18, 8700 Leoben, Austria e Institute of Physics, Karl-Franzens University Graz, Universitätsplatz 5, 8010 Graz, Austria |
| |
Abstract: | A para-sexiphenyl monolayer of near up-right standing molecules (nominal thickness of 30 Å) is investigated in-situ by X-ray diffraction using synchrotron radiation and ex-situ by atomic force microscopy. A terrace like morphology is observed, the step height between the terraces is approximately one molecular length. The monolayer terraces, larger than 20 μm in size, are extended along the 0 0 1] direction of the TiO2(1 1 0) substrate i.e. along the Ti-O rows of the reconstructed substrate surface. The structure of the monolayer and its epitaxial relationship to the substrate is determined by grazing incidence X-ray diffraction. Extremely sharp diffraction peaks reveal high crystalline order within the monolayer, which was found to have the bulk structure of sexiphenyl. The monolayer terraces are epitaxially oriented with the (0 0 1) plane parallel to the substrate surface (out-of-plane order). Four epitaxial relationships are observed. This in-plane alignment is determined by the arrangement of the terminal phenyl rings of the sexiphenyl molecules parallel to the oxygen rows of the substrate. |
| |
Keywords: | Organic epitaxy Thin film structure Grazing incidence X-ray diffraction Atomic force microscopy |
本文献已被 ScienceDirect 等数据库收录! |
|