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Updated: Nov 1, 2025

Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Chemical Identification and Bond Control of π-Skeletons in a Coupling Reaction
Chi Zhang1, Rafael B Jaculbia1, Yusuke Tanaka2,3
1Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Abstract:
Highly unsaturated π-rich carbon skeletons afford versatile tuning of structural and optoelectronic properties of low-dimensional carbon nanostructures. However, methods allowing more precise chemical identification and controllable integration of target sp-/sp2-carbon skeletons during synthesis are required. Here, using the coupling of terminal alkynes as a model system, we demonstrate a methodology to visualize and identify the generated π-skeletons at the single-chemical-bond level on the surface, thus enabling further precise bond control. The characteristic electronic features together with localized vibrational modes of the carbon skeletons are resolved in real space by a combination of scanning tunneling microscopy/spectroscopy (STM/STS) and tip-enhanced Raman spectroscopy (TERS). Our approach allows single-chemical-bond understanding of unsaturated carbon skeletons, which is crucial for generating low-dimensional carbon nanostructures and nanomaterials with atomic precision.
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