High-Resolution Spectroscopy of Jet-Cooled Naphthalene: the 000 and 3301 Bands of the Ã1B1u←X̃1Ag Transition

✍ Scribed by Duck-Lae Joo; Rika Takahashi; John O'Reilly; Hajime Katô; Masaaki Baba

• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 321 KB
• Volume: 215
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2002.8625

✦ Synopsis

Rotationally resolved excitation spectra of the 0 0 0 and 33 1 0 bands of the Ã1 B 1u ← X 1 A g electronic transition of naphthalene were measured by a frequency-doubled single-mode tunable laser and a jet-cooled collimated molecular beam. The observed linewidth was 18 MHz, and the absolute wavenumber was determined with an accuracy of better than 0.0002 cm -1 . The molecular constants of the X 1 A g (v = 0), Ã1 B 1u (v = 0), and Ã1 B 1u (v 33 = 1) levels were determined and represent the most accurate measurements to date. Three rotational constants were sufficient to fit 3386 lines of J = 1-43 and K a = 0-21 with a standard deviation 0.0002 cm -1 . This indicates that the molecular structures are rigid both in the X 1 A g and Ã1 B 1u states. When a magnetic field was applied, spectral line broadening was observed for levels with small K a value in the Ã1 B 1u (v 33 = 1) state, and the Zeeman splitting was observed to increase with increasing J . No broadening, however, was observed in the 0 0 0 band up to H = 0.65 T.