Graphical Abstract

Voltage-controlled conductance and switching induced by single molecules or atoms are ideally studied in scanning tunneling microscope (STM) tunnel junctions. While the objects under consideration are mostly used in their original form, little is known of the possibilities of in situ adjustments of their properties. Here, we evidence properties of a tunnel junction made of a Ce atom/cluster built by atomic manipulation on Au(111) at a temperature of 4.6 K in the presence of H2. The conductance through the object is characterized by a switching voltage corresponding to an opening or closing of an inelastic electron tunneling conductance channel at 50 mV for a Ce atom and 140 mV for a Ce cluster and by charging. We demonstrate that the electronic properties of an STM junction can be engineered in a simple way by in situ guiding of the H2 pinning at an atomic cluster.
Troisi, A.; Ratner, M. A. Molecular signatures in the transport properties of molecular wire junctions: What makes a junction "molecular". Small 2006, 2, 172-181.
Zhang, J. L.; Zhong, J. Q.; Lin, J. D.; Hu, W. P.; Wu, K.; Xu, G. Q.; Wee, A. T. S.; Chen, W. Towards single molecule switches. Chem. Soc. Rev. 2015, 44, 2998-3022.
Wang, Y. F.; Kröger, J.; Berndt, R.; Hofer, W. A. Pushing and pulling a Sn ion through an adsorbed phthalocyanine molecule. J. Am. Chem. Soc. 2009, 131, 3639-3643.
Weight, S.; Busse, C.; Petersen, L.; Rauls, E.; Hammer, B.; Gothelf, K. V.; Besenbacher, F.; Linderoth, T. R. Chiral switching by spontaneous conformational change in adsorbed organic molecules. Nat. Mater. 2006, 5, 112-117.
Qui, X. H.; Nazin, G. V.; Ho, W. Mechanisms of reversible conformational transitions in a single molecule. Phys. Rev. Lett. 2004, 93, 196806.
Leoni, T.; Guillermet, O.; Walch, H.; Langlais, V.; Scheuermann, A.; Bonvoisin, J.; Gauthier, S. Controlling the charge state of a single redox molecular switch. Phys. Rev. Lett. 2011, 106, 216103.
Gopakumar, T. G.; Matino, F.; Naggert, H.; Bannwarth, A.; Tuczek, F.; Berndt, R. Electron-induced spin crossover of single molecules in a bilayer on gold. Angew. Chem., Int. Ed. 2012, 51, 6262-6266.
Wu, S. W.; Ogawa, N.; Nazin, G. V.; Ho, W. Conductance hysteresis and switching in a single-molecule junction. J. Phys. Chem. C 2008, 112, 5241-5244.
Auwärter, W.; Seufert, K.; Bischoff, F.; Ecija, D.; Vijayaraghavan, S.; Joschi, S.; Klappenberger, F.; Samudrala, N.; Barth, J. V. A surface-anchored molecular four-level conductance switch based on single proton transfer. Nat. Nanotechnol. 2012, 7, 41-46.
Eigler, D. M., Lutz, C. P.; Rudge, W. E. An atomic switch realized with the scanning tunnelling microscope. Nature 1991, 352, 600-603.
Repp, J.; Meyer, G.; Olsson, F. E.; Person, M. Controlling the charge state of individual gold adatoms. Science 2004, 305, 493-495.
Wang, G. F.; Peng, Q.; Li, Y. D. Lanthanide-doped nanocrystals: Synthesis, optical-magnetic properties, and applications. Acc. Chem. Res. 2011, 44, 322-332.
Rodriguez, J. A.; Ma, S.; Liu, P.; Hrbek, J.; Evans, J.; Pérez, M. Activity of CeOx and TiOx nanoparticles grown on Au(111) in the water-gas shift reaction. Science 2007, 318, 1757-1760.
Ma, S.; Zhao, X.; Rodriguez, J. A.; Hrbek, J. STM and XPS study of growth of Ce on Au(111). J. Phys. Chem. C 2007, 111, 3685-3691.
Li, J. T.; Schneider, W. D.; Berndt, R.; Delley, B. Kondo scattering observed at a single magnetic impurity. Phys. Rev. Lett. 1998, 80, 2893-2896.
Pivetta, M.; Ternes, M.; Patthey, F.; Schneider, W. D. Diatomic molecular switches to enable the observation of very-low-energy vibrations. Phys. Rev. Lett. 2007, 99, 126104.
Hofer, W. A.; Teobaldi, G.; Lorente, N. Creating pseudo- Kondo resonances by field-induced diffusion of atomic hydrogen. Nanotechnology 2008, 19, 305701.
Zhang, Z. W.; Zheng, W. T.; Jiang, Q. Hydrogen adsorption on Ce/BNNT systems: A DFT study. Int. J. Hydrogen Energy 2012, 37, 5090-5099.
Gupta, J. A.; Lutz, C. P.; Heinrich, A. J.; Eigler, D. M. Strongly coverage-dependent excitations of adsorbed molecular hydrogen. Phys. Rev. B 2005, 71, 115416.
Thijssen, W. H. A.; Djukic, D.; Otte, A. F.; Bremmer, R. H.; van Ruitenbeek, J. M. Vibrationally induced two-level systems in single-molecule junctions. Phys. Rev. Lett. 2006, 97, 226806.
Tal, O.; Krieger, M.; Leerink, B.; van Ruitenbeek, J. M. Electron-vibration interaction in single-molecule junctions: From contact to tunneling regimes. Phys. Rev. Lett. 2008, 100, 196804.
Trouwborst, M. L.; Huisman, E. H.; van der Molen, S. J.; van Wees, B. J. Bistable hysteresis and resistance switching in hydrogen-gold junctions. Phys. Rev. B 2009, 80, 081407.
Li, S. W.; Yu, A.; Toledo, F.; Han, Z. M.; Wang, H.; He, H. Y.; Wu, R. Q.; Ho, W. Rotational and vibrational excitations of a hydrogen molecule trapped within a nanocavity of tunable dimension. Phys. Rev. Lett. 2013, 111, 146102.
Natterer, F. D.; Patthey, F.; Brune, H. Distinction of nuclear spin states with the scanning tunneling microscope. Phys. Rev. Lett. 2013, 111, 175303.
Lotze, C.; Corso, M.; Franke, K. J.; von Oppen, F.; Pascual, J. I. Driving a macroscopic oscillator with the stochastic motion of a hydrogen molecule. Science 2012, 338, 779-782.
Yang, K.; Xiao, W. D.; Liu, L. W.; Fei, X. M.; Chen, H.; Du, S. X.; Gao, H. J. Construction of two-dimensional hydrogen clusters on Au(111) directed by phthalocyanine molecules. Nano Res. 2014, 7, 79-84.
Cao, X. Y.; Dolg, M. Electronic structure of lanthanide dimers. Mol. Phys. 2003, 101, 1967-1976.
Roos, B. O.; Lindh, R.; Malmqvist, P. A.; Veryazov, V.; Widmark, P. O. New relativistic atomic natural orbital basis sets for lanthanide atoms with applications to the Ce diatom and LuF3. J. Phys. Chem. A 2008, 112, 11431-11435.
Fernández-Torres, L. C.; Sykes, E. C. H.; Nanayakkara, S. U.; Weiss, P. S. Dynamics and spectroscopy of hydrogen atoms on Pd{111}. J. Phys. Chem. B 2006, 110, 7380-7384.
den Broeder, F. J. A.; van der Molen, S. J.; Kremers, M.; Huiberts, J. N.; Nagengast, D. G.; van Gogh, A. T. M.; Huisman, W. H.; Koeman, N. J.; Dam, B.; Rector, J. H. et al. Visualization of hydrogen migration in solids using switchable mirrors. Nature 1998, 394, 656-658.
Blanksby, S. J.; Ellison, G. B. Bond dissociation energies of organic molecules. Acc. Chem. Res. 2003, 36, 255-263.
Olson, F. E.; Paavilainen, S.; Persson, M.; Repp, J.; Meyer, G. Multiple charge states of Ag atoms on ultrathin NaCl films. Phys. Rev. Lett. 2007, 98, 176803.