Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 68: Focussed session: Functional molecules at surfaces III
O 68.5: Vortrag
Donnerstag, 29. März 2012, 12:15–12:30, A 053
First-principles calculations on dependence of electron transport through molecular junctions on the anchoring groups — •Shigeru Tsukamoto, Vasile Caciuc, Nicolae Atodiresei, and Stefan Blügel — Peter Grünberg Institut & Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, D-52425 Jülich
Molecular electronics is exciting by the perspective that various types of electric properties are potentially realized only by single molecules with unique electronic structures. In particular, the anchoring groups in a molecular junction, which link a molecule to an electrode, are recognized as an important part to control the electron conductivity.
Here, by means of first-principles calculations we report how the anchoring groups of molecular junctions affect the electron transmissions. The systems used here are M–R–C6H4–R–M, where M is a Cu or Au electrode, and R is an anchoring group as R=S, COO, BOO, NOO.
The transport calculations have revealed significant differences in the electron transmissions of the four molecular junctions: The molecular junctions with S and BOO anchoring groups have finite electron transmissions at the Fermi level, and the transmission of the system with the BOO group changes rapidly at the energies above and below the Fermi level. For the molecular junctions with COO and NOO anchoring groups, the electron transmissions at the Fermi level are small but they increase at the energies above and below the Fermi level, respectively. The difference in the electron transmissions obviously originates from the difference in the anchoring groups, and the variation in electric functionality of single molecular junctions is suggested.