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Published on: May 13, 2017
Measuring the distance between two mercapto groups with an optical molecular ruler on the nanometer scale
Fan Gao1, Erdong Yao, Wei Wang
1Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry, Peking University, Beijing, 100871, China.
Abstract:
We have developed an absorption spectrum based molecular ruler that measures the distance between two mercapto groups. The conformation of the molecular rulers changes with the distance, which induces an absorption spectrum change. DFT calculation has been carried out to elucidate the relation between the molecular conformation and the absorption spectrum. With this simple method, we can estimate the distance between two mercapto groups on the scale of 0.4-1 nm. This method can also be used to monitor conformation transition, which is demonstrated by a silver ion titration experiment.
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