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Updated: Jun 11, 2026

Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
07:44

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在金属和半导体单壁碳纳米管上的碳共振的固态13C核磁共振赋值

Chaiwat Engtrakul1, Mark F Davis, Kevin Mistry

  • 1National Renewable Energy Laboratory, Golden, Colorado 80401, USA. Chaiwat.Engtrakul@nrel.gov

Journal of the American Chemical Society
|July 3, 2010
PubMed
概括

固态碳-13核磁共振 (13C NMR) 光谱学有效地区分金属 (m-SWNT) 和半导体 (s-SWNT) 单壁纳米管. 这种技术提供了一种敏感的方法来分析基于其独特的化学转移的SWNT混合物.

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The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
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When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
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