UV Laser Spectroscopy Using the Velocity-Modulation Technique: New Hot Bands of the B2Σ+u–X2Σ+g System of N+2

✍ Scribed by D. Collet; T.R. Huet

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 310 KB
• Volume: 197
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1999.7894

✦ Synopsis

The laser absorption spectroscopy of molecular ions using the velocity-modulation technique has been employed in the UV region. The absorption source was a cw single-mode laser beam from an extra-cavity frequency doubling unit associated with a dye laser. The high-resolution spectrum of the First Negative system B 2 ⌺ u ϩ -X 2 ⌺ g ϩ of N 2 ϩ has been studied. The N 2 ϩ ions were produced with an electric discharge in a flowing gas mixture of He/N 2 . Seven vibrational bands of the ⌬v ϭ 2 sequence (vЈ ϭ 2-8) have been observed in the region between 30 000 and 30 600 cm Ϫ1 , and five of them for the first time at high resolution (vЈ ϭ 2-4, 6, 7). A set of 770 lines have been assigned; among them are several extra -lines belonging to the A 2 ⌸ u -X 2 ⌺ g ϩ system. A standard model has been used to consider the perturbations between the rovibrational levels of the B 2 ⌺ u ϩ and A 2 ⌸ u states. An improved set of deperturbed constants and effective interaction parameters were derived for the v B ϭ 3-v A ϭ 14 and v B ϭ 7-v A ϭ 20 complexes.