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Updated: Jul 21, 2026

Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
Bias-dependent visualization of electron donor (D) and electron acceptor (A) moieties in a chiral DAD triad molecule
Atsushi Miura1, Zhijian Chen, Hiroshi Uji-I
1Katholieke Universiteit Leuven, Department of Chemistry, Celestijnenlaan 200 F, B-3001 Leuven, Belgium.
Abstract:
The 2D crystal lattice structure and bias-dependent contrast of a chiral electron donor-acceptor-donor triad system, composed of two oligo(p-phenylene vinylene) electron donors and a perylenediimide electron acceptor (OPV4-PDI-OPV4), have been studied by means of scanning tunneling microscopy (STM) at the liquid-graphite interface. OPV4-PDI-OPV4 is ordered in rows and forms a well-ordered 2D crystal lattice structure. The electrical properties of the donor and acceptor parts are distinguished by the contrast in bias-dependent STM imaging.
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