Ultraviolet Absorption in Amorphous Carbons: Polycyclic Aromatic Hydrocarbons and the 2175 Å Extinction Feature

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

17

Ism: Dust, Extinction, Ism: Lines And Bands, Ism: Molecules, Ultraviolet: Ism

Scientific paper

Amorphous carbons have been prepared by plasma deposition in a vacuum and in the presence of a variety of gases. On subsequent heating in a vacuum, ultraviolet absorption spectra of certain of these materials show the development of a feature centered at 2175 Å (4.6 μm-1). We find that the spectrum of amorphous carbon prepared from a hydrogen plasma provides a good match to the interstellar spectrum. In addition, infrared spectra and high-resolution imaging of these deposits indicate the presence of polycyclic aromatic hydrocarbon (PAH) islands in these solids, suggesting that the UV absorption feature can be attributed to the π-π* plasmon resonance in PAH components having structures similar to coronene. An excellent fit to the laboratory data is obtained with the calculated π-π* plasmon in dehydrogenated coronene, C24. Our data suggest that relatively small dehydrogenated PAH molecules similar to molecular groups seen in amorphous carbon may be the origin of the interstellar extinction feature at 2175 Å.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Ultraviolet Absorption in Amorphous Carbons: Polycyclic Aromatic Hydrocarbons and the 2175 Å Extinction Feature does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ultraviolet Absorption in Amorphous Carbons: Polycyclic Aromatic Hydrocarbons and the 2175 Å Extinction Feature, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ultraviolet Absorption in Amorphous Carbons: Polycyclic Aromatic Hydrocarbons and the 2175 Å Extinction Feature will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1061519

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.