Abstract
Folding of molecules is an essential process in nature,and various molecular machines achieve their chemical and mechanical function via controlled folding of molecular conformations.The electric field offers a unique strategy to drive the folding of molecular conformation and to control charge transport through single molecules but remains unexplored.The single-molecule break junction technique provides access to detect the conformational changes via the monitoring of single-molecule conductance,and the electric field between two metal electrodes with nanoscale spacing can provide an extremely strong to achieve in-situ control and detection of molecular folding at the single-molecule level.Here,we use the electric field to control the single-molecule folding using the scanning tunneling microscope break junc-tion(STM-BJ)technique.The electric fields induced folding could lead to a～1400％conductance change of the single-molecule junctions,and the folding/unfolding process can be in-situ switched at the scale of milliseconds.DFT calculations suggest the conformational control originates from the electric field-induced charge injection,and the formation of homoconjugated conformation with the overlapped or-bitals.This work provides the first demonstration of electric field-driven molecular folding,which is es-sential for the understanding of molecular machines in nature and for the design of artificial molecular machines.
NETL
NSTL
维普
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