Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 89: Inorganic/Organic Interfaces: Molecular Switches
O 89.11: Vortrag
Donnerstag, 19. März 2015, 17:30–17:45, MA 043
Intramolecular Dipole of Merocyanine Probed by Local Contact Potential Difference Measurements — •Nils Krane1, Christian Lotze1, Xianwen Chen1, José Ignacio Pascual1,2,3, and Katharina Franke1 — 1Freie Universität Berlin, Berlin, Germany — 2CIC nanoGUNE, San Sebastián, Spain — 3Ikerbasque, Basque Foundation for Science, Bilbao, Spain
In gas phase and solution 1,3,3-Trimethylindolino-6’-nitrobenzopyrylospiran can be switched reversibly by light and temperature to its merocyanine form. This form has been shown to exhibit an intramolecular dipole [1].
When adsorbed on a metal surface the switching back to the spiropyran form is inhibited [2].
Charge redistribution and screening may considerably alter the expected dipole behavior of the merocyanine form.
Utilizing combined low-temperature scanning tunneling microscopy and dynamic atomic force microscopy, we characterize the adsorption of merocyanine on Au(111). The intramolecular charge distribution is measured by the local contact potential difference (LCPD) [3]. The vertical and lateral distribution of the LCPD hints at the persistence of an intramolecular dipole.
Lapienis-Grochowska et al., JCS, Far.Trans. 2 1979, 75, 312
Marten Piantek et al., J. Am. Chem. Soc. 2009, 131, 12729
Mohn et al., Nature Nanotechnology 2012, 7, 227-231