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Title: Molecular structure and chiral separation in {alpha}-sexithiophene ultrathin films on Au(111): Low-energy electron diffraction and scanning tunneling microscopy

Abstract

The adsorption of the {pi}-conjugated organic molecule {alpha}-sexithiophene which is widely used in molecular electronics has been studied on Au(111) by low-energy electron diffraction and scanning tunneling microscopy. For monolayer adsorption at room temperature, large, well-ordered domains of flat-lying molecules which arrange in molecular rows are observed. A detailed structure analysis reveals an incommensurate, line-on-line oriented monolayer with one molecule per unit cell. In contrast to the behavior in the three-dimensional bulk structure, flat-lying adsorption introduces molecular chirality: Right- and left-handed molecules separate into domains of different orientations which are mirror symmetric with respect to the [112] substrate direction. Details of the adlayer structure and the chiral self-recognition can be rationalized based on the van der Waals contour of the adsorbed molecules.

Authors:
; ; ;  [1]
  1. Institute of Physics, Martin-Luther-Universitaet Halle-Wittenberg, Halle (Germany)
Publication Date:
OSTI Identifier:
20951435
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevB.75.195439; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADSORPTION; CHIRALITY; ELECTRON DIFFRACTION; LAYERS; MOLECULAR STRUCTURE; ORGANIC SEMICONDUCTORS; SCANNING TUNNELING MICROSCOPY; TEMPERATURE RANGE 0273-0400 K; THIN FILMS; THREE-DIMENSIONAL CALCULATIONS; VAN DER WAALS FORCES

Citation Formats

Kiel, Mario, Duncker, Klaus, Hagendorf, Christian, and Widdra, Wolf. Molecular structure and chiral separation in {alpha}-sexithiophene ultrathin films on Au(111): Low-energy electron diffraction and scanning tunneling microscopy. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.195439.
Kiel, Mario, Duncker, Klaus, Hagendorf, Christian, & Widdra, Wolf. Molecular structure and chiral separation in {alpha}-sexithiophene ultrathin films on Au(111): Low-energy electron diffraction and scanning tunneling microscopy. United States. doi:10.1103/PHYSREVB.75.195439.
Kiel, Mario, Duncker, Klaus, Hagendorf, Christian, and Widdra, Wolf. Tue . "Molecular structure and chiral separation in {alpha}-sexithiophene ultrathin films on Au(111): Low-energy electron diffraction and scanning tunneling microscopy". United States. doi:10.1103/PHYSREVB.75.195439.
@article{osti_20951435,
title = {Molecular structure and chiral separation in {alpha}-sexithiophene ultrathin films on Au(111): Low-energy electron diffraction and scanning tunneling microscopy},
author = {Kiel, Mario and Duncker, Klaus and Hagendorf, Christian and Widdra, Wolf},
abstractNote = {The adsorption of the {pi}-conjugated organic molecule {alpha}-sexithiophene which is widely used in molecular electronics has been studied on Au(111) by low-energy electron diffraction and scanning tunneling microscopy. For monolayer adsorption at room temperature, large, well-ordered domains of flat-lying molecules which arrange in molecular rows are observed. A detailed structure analysis reveals an incommensurate, line-on-line oriented monolayer with one molecule per unit cell. In contrast to the behavior in the three-dimensional bulk structure, flat-lying adsorption introduces molecular chirality: Right- and left-handed molecules separate into domains of different orientations which are mirror symmetric with respect to the [112] substrate direction. Details of the adlayer structure and the chiral self-recognition can be rationalized based on the van der Waals contour of the adsorbed molecules.},
doi = {10.1103/PHYSREVB.75.195439},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 19,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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