SPM Imaging of Trinaphthylene Molecular States on a Hydrogen Passivated Ge(001) Surface
We report on studies concerning individual trinaphthylene molecules (Y molecules) deposited and anchored on the hydrogenated Ge(001):H surface. The characterization of single Y molecules has been performed by means of cryogenic temperature STM imaging using conventional STM tungsten tips and tuning fork-based sensors. In the latter case, a qPlus sensor facilitated simultaneous STM and NC-AFM measurements and thus molecular states were probed by both tunneling current and atomic forces concurrently. We show that the molecules are physisorbed, thus weakly interacting with the substrate. Contrary to the measurements on hydrogenated silicon, for planar aromatic molecules on the hydrogenated germanium, both empty and filled molecular states could be probed by STM.
KeywordsHeptastarphene molecules Scanning tunneling microscopy Non-contact atomic force microscopy Molecular state imaging Electronic decoupling of molecules on surfaces Hydrogen passivated germanium Ge(001): H
This research was supported by the 7th Framework Programme of the European Union Collaborative Project ICT (Information and Communication Technologies) “Atomic Scale and Single Molecule Logic Gate Technologies” (ATMOL), Contract No. FP7-270028. The experimental part of the research was carried out with equipment purchased with financial support from the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (Contract No. POIG.02.01.00-12-023/08).
- 4.Soe, W.-H., Manzano, C., Renaud, N., De Mendoza, P., De Sarkar, A., Ample, F., Hliwa, M., Echavarren, A.M., Chandrasekhar, N., Joachim, C.: Manipulating molecular quantum states with classical metal atom inputs: demonstration of a single molecule NOR logic gate. ACS Nano 5, 1436–1440 (2012)CrossRefGoogle Scholar
- 6.Gruyters, M., Pingel, T., Gopakumar, T.G., Néel, N., Schütt, Ch., Köhler, F., Herges, R., Berndt, R.: Electronic ground-state and orbital ordering of iron phthalocyanine on H/Si(111) unraveled by spatially resolved tunneling spectroscopy. J. Phys. Chem. C 116, 20882–20886 (2012)CrossRefGoogle Scholar
- 8.Horcas, I., Fernández, R., Gómez-Rodríguez, J. M., Colchero, J., Gómez-Herrero, J., Baro, A. M.: WSXM: a software for scanning probe microscopy and a tool for nanotechnology. Rev. Sci. Instr. 78, 013705 (2007)Google Scholar