Host: The Japan Society of Vacuum and Surface Science
We developed a methodology to discriminate chirality of a single molecule on a solid surface based on STM using molecular tips. A chiral molecule was used as a tip molecule to measure electron transport with the sample molecule on a metal substrate. Axially chiral binaphthyl derivative (BINAP) served as sample molecules. A break-junction technique was employed to determine the conductance of the single molecular assembly composed of the tip and sample molecules. It was found that the conductance depends on the stereochemistry of the sample molecule, thereby achieving chiral recognition on a single-molecule basis. It was demonstrated that the lifetime of the molecular assembly reflects its stabilization energy calculated based on density functional theory. Thus, we conclude that the stereoselectivity originates from the diastereomeric interaction between the tip and sample.
