jp9b10232_si_001.pdf (2.87 MB)
Conductance Behavior of Tetraphenyl-Aza-BODIPYs
journal contribution
posted on 2020-03-17, 18:03 authored by Andrei Markin, Ali K. Ismael, Ross J. Davidson, David C. Milan, Richard J. Nichols, Simon J. Higgins, Colin J. Lambert, Yu-Ting Hsu, Dmitry S. Yufit, Andrew BeebyWe
studied the electrical conductance of single-molecule junctions
formed from molecular wires with four anchor groups. Three tetraphenyl-aza-BODIPYs
with four or two thiomethyl anchor groups were synthesized, and their
single-molecule conductance was measured using break-junction-STM.
Using DFT based calculations these compounds were shown to display
a combination of a high and low conductance, depending on the molecule’s
connectivity in the junction. A scissor correction is employed to
obtain the corrected HOMO–LUMO gaps and a tight binding model
(TBM) is used to highlight the role of transport through the pi system
of the tetraphenyl-aza-BODIPY central unit. The three higher-conductance
geometries follow the sequence 3 > 4 > 2, which demonstrates
that
their conductances are correlated with the number of anchors.