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Updated: Jul 6, 2026
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Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Electronic spectroscopy of carbon chains
Evan B Jochnowitz1, John P Maier
1Department of Chemistry, University of Basel, CH-4056 Basel, Switzerland. evan.jochnowitz@unibas.ch
Annual Review of Physical Chemistry
|April 9, 2008
Summary
Odd-numbered carbon chains, particularly those with 17 or more atoms, show electronic transitions matching diffuse interstellar band (DIB) absorptions. Larger carbon rings also exhibit similarities to DIBs, suggesting potential carriers in space.
Area of Science:
- Astrochemistry
- Spectroscopy
- Physical Chemistry
Background:
- Diffuse interstellar bands (DIBs) are observed astronomical absorption features.
- The molecular carriers of DIBs remain largely unidentified.
- Gas-phase electronic spectra of carbon-chain systems are crucial for DIB carrier identification.
Purpose of the Study:
- To investigate the electronic spectra of various carbon-chain systems.
- To compare laboratory spectral data with astronomical DIB measurements.
- To identify potential carbon-based molecular carriers of DIBs.
Main Methods:
- Cavity ringdown absorption spectroscopy
- Photofragmentation techniques utilizing ion trap cooling
- High-resolution spectral analysis
Main Results:
- Odd-numbered carbon chains (n=17, 19, ...) exhibit strong electronic transitions in the 400-900 nm range, coinciding with DIBs.
- Larger bare carbon rings, like C(18), show high-resolution spectral similarities to some DIBs.
- Electronic spectra of metal-containing carbon chains were also analyzed.
Conclusions:
- Odd-numbered carbon chains are strong candidates for carrying specific DIBs.
- Larger carbon rings may also contribute to the observed DIB spectrum.
- Further investigation of metal-containing carbon chains could reveal additional DIB carriers.
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