INFRARED SPECTRA OF ISOLATED PROTONATED POLYCYCLIC AROMATIC HYDROCARBON MOLECULES

Journal Article · Fri Nov 20 04:00:00 EST 2009 · Astrophysical Journal (Online)

DOI:https://doi.org/10.1088/0004-637X/706/1/L66· OSTI ID:21378204

Knorke, Harald; Langer, Judith; Dopfer, Otto ^[1]; Oomens, Jos ^[2]

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1. Institut fuer Optik und Atomare Physik, Technische Universitaet Berlin, Hardenbergstrasse 36, D-10623 Berlin (Germany)
2. FOM Institute for Plasma Physics, Rijnhuizen, P.O. Box 1207, 3430BE Nieuwegein (Netherlands)

Gas-phase infrared (IR) spectra of larger protonated polycyclic aromatic hydrocarbon molecules, H{sup +}PAH, have been recorded for the first time. The ions are generated by electrospray ionization and spectroscopically assayed by IR multiple-photon dissociation (IRMPD) spectroscopy in a Fourier transform ion cyclotron resonance mass spectrometer using a free electron laser. IRMPD spectra of protonated anthracene, tetracene, pentacene, and coronene are presented and compared to calculated IR spectra. Comparison of the laboratory IR spectra to an astronomical spectrum of the unidentified IR emission (UIR) bands obtained in a highly ionized region of the interstellar medium provides for the first time compelling spectroscopic support for the recent hypothesis that H{sup +}PAHs contribute as carriers of the UIR bands.

• OSTI ID: 21378204
• Journal Information: Astrophysical Journal (Online), Journal Name: Astrophysical Journal (Online) Journal Issue: 1 Vol. 706; ISSN 1538-4357
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ANTHRACENE
AROMATICS
BOSONS
CATIONS
CHARGED PARTICLES
CONDENSED AROMATICS
CYCLOTRON RESONANCE
DISSOCIATION
ELEMENTARY PARTICLES
EMISSION
FOURIER TRANSFORMATION
FREE ELECTRON LASERS
HYDROCARBONS
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
INFRARED SPECTRA
INTEGRAL TRANSFORMATIONS
ION CYCLOTRON-RESONANCE
IONIZATION
IONS
LASERS
MASS SPECTROMETERS
MASSLESS PARTICLES
MEASURING INSTRUMENTS
MOLECULES
ORGANIC COMPOUNDS
PENTACENE
PHOTONS
POLYCYCLIC AROMATIC HYDROCARBONS
RESONANCE
SPECTRA
SPECTROMETERS
SPECTROSCOPY
TETRACENE
TRANSFORMATIONS