Formation and evolution of single-molecule junctions.
We analyze the formation and evolution statistics of single-molecule junctions bonded to gold electrodes using amine, methyl sulfide, and dimethyl phosphine link groups by measuring conductance as a function of junction elongation. For each link, the maximum elongation and formation probability increase with molecular length, strongly suggesting that processes other than just metal-molecule bond breakage play a key role in junction evolution under stress. Density functional theory calculations of adiabatic trajectories show sequences of atomic-scale changes in junction structure, including shifts in the attachment point, that account for the long conductance plateau lengths observed.
Kamenetska
M
M
Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY, USA.
Koentopp
M
M
Whalley
A C
AC
Park
Y S
YS
Steigerwald
M L
ML
Nuckolls
C
C
Hybertsen
M S
MS
Venkataraman
L
L