Rotation-libration in a hierarchic supramolecular rotor-stator system: arrhenius activation and retardation by local interaction.
Fourfold symmetric zinc-octaethylporphyrin (OEP) has been incorporated in the holes of the hexagonal molecular network generated by thermal dehydrogenation of 4,9-diaminoperylene-quinone-3,10-diimine (DPDI) on a Cu(111) surface and displayed hindered rotation; the reorganization between the potential minima, a rotation-libration, which is characterized by an activation energy of ED=0.17+/-0.03 eV, has been monitored in the STM tunnelling currents as a bi-state "switching".
Wahl
Markus
M
NCCR Nanoscale Science and Institute of Physics, University of Basel, Klingelbergstr. 82, 4056 Basel, Switzerland.
Stöhr
Meike
M
Spillmann
Hannes
H
Jung
Thomas A
TA
Gade
Lutz H
LH