The interstellar chemistry of PAH cations

Theodore P. Snow (), Valery Le Page, Yeghis Keheyan and Veronica M. Bierbaum
Additional contact information
Theodore P. Snow: Center for Astrophysics and Space Astronomy, University of Colorado
Valery Le Page: University of Colorado
Yeghis Keheyan: Istituto di Chimica Nucleare del CNR
Veronica M. Bierbaum: University of Colorado

Nature, 1998, vol. 391, issue 6664, 259-260

Abstract: Abstract Diffuse interstellar bands (DIBs) are mysterious absorption lines in the optical spectra of stars, and have been known for 75 years1. Although it is widely believed2,3,4 that they arise from gas-phase organic molecules (rather than from dust grains) in the interstellar medium, no consensus has been reached regarding their precise cause. The realization that many emission features in astronomical infrared spectra probably arise from polycyclic aromatic hydrocarbons5,6,7,8 (PAHs), which may themselves be very abundant in the interstellar medium, has led to the suggestion that ionized PAHs might be the source of the DIBs9,10,11,12. Laboratory investigations have revealed that small, positively charged PAHs in matrices have absorption features that bear some resemblance to DIBs13,14,15, but no clear identification of any DIB with any specific PAH cation has yet been made. Here we report a laboratory study of the chemical reactivity of PAH cations (C6H6+, C10H8+and C16H10+) in the gas phase. We find that these PAH cations are very reactive, and are therefore unlikely to survive in high abundances in the interstellar medium. Rather, such molecules will react rapidly with hydrogen, and we therefore suggest that the resulting protonated PAH cations (and species derived from them) should become the focus of future searches for a correspondence between molecular absorption features and the DIBs.

Date: 1998
References: Add references at CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
https://www.nature.com/articles/34602 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:391:y:1998:i:6664:d:10.1038_34602

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/34602

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().