Macroscopic and nanoscopic current-voltage measurements revealasymmetries in the DC electricalconductivity through Langmuir-Blodgett multilayers and evenmonolayers of
![](/images/gifchars/gamma.gif)
-(
n-hexadecyl)quinolinumtricyanoquinodimethanide, C
16H
33Q-3CNQ (
5).These asymmetries are due to a transition of the ground-statezwitterion toan excited-state conformer which is probably neutral. Unimolecularelectrical rectification by monolayers of
5 isunequivocally confirmed.