Visible absorptions of potential diffuse ISM hydrocarbons: C${}_9$H${}_9$ and C${}_9$H${}_5$ radicals

Abstract

The laboratory detection of previously unobserved resonance-stabilized C${}_9$H${}_5$ and C${}_9$H${}_9$ radicals in the supersonic expansion of a hydrocarbon discharge source is reported. The radicals are tentatively assigned as acetylenic-substituted cyclopentadienyl C${}_9$H${}_5$ and vinyl-substituted benzyl C${}_9$H${}_9$ species. They are found to feature visible absorption bands that coincide with a few very weak diffuse interstellar bands toward HD183143 and HD204827.

5 figures, 3 tables

References in corpus (3)

• A Catalog of Diffuse Interstellar Bands in the Spectrum of HD 204827
• Studies of the Diffuse Interstellar Bands. III. HD 183143
• Electronic spectra of linear HC${}_5$H and cumulene carbene H${}_2$C${}_5$