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Updated: May 21, 2026

Single-Molecule Förster Resonance Energy Transfer Methods for Real-Time Investigation of the Holliday Junction Resolution by GEN1
Published on: September 18, 2019
Charge transport characteristics of diarylethene photoswitching single-molecule junctions
Youngsang Kim1, Thomas J Hellmuth, Dmytro Sysoiev
1Department of Physics, University of Konstanz, 78457 Konstanz, Germany.
Abstract:
We report on the experimental analysis of the charge transport through single-molecule junctions of the open and closed isomers of photoswitching molecules. Sulfur-free diarylethene molecules are developed and studied via electrical and optical measurements as well as density functional theory calculations. The single-molecule conductance and the current-voltage characteristics are measured in a mechanically controlled break-junction system at low temperatures. Comparing the results with the single-level transport model, we find an unexpected behavior of the current-dominating molecular orbital upon isomerization. We show that both the side chains and end groups of the molecules are crucial to understand the charge transport mechanism of photoswitching molecular junctions.
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