A Study of theX2Σ+andA2Π States of SiO+Using Fast-Ion-Beam Laser Spectroscopy

✍ Scribed by S.D. Rosner; R. Cameron; T.J. Scholl; R.A. Holt

• Book ID: 102974191
• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 514 KB
• Volume: 189
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1997.7522

✦ Synopsis

We have observed for the first time the (4, 4), (4, 3), and (5, 4) bands of the B 2 S / -X 2 S / system of SiO / using laser-induced fluorescence spectroscopy on a fast SiO / beam. These data contain avoided crossings between the X 2 S / and A 2 P states, as well as a few extra lines belonging to the (3, 2), (4, 2), and (5, 3) bands of the B 2 S / -A 2 P system. They enlarge considerably a previously measured data set consisting of almost 1400 lines of the (0, 0), (1, 1), (2, 2), (3, 3), (1, 0), (2, 1), and (3, 2) bands of the B-X system and 66 lines of the (2, 0) V Å 1 2 subband of the B 2 S / -A 2 P system. The entire data set of 2378 assigned lines has been fit simultaneously to a model Hamiltonian in which many closely overlapped levels of the X and A states are handled by direct diagonalization. The newly observed avoided crossings between the X and A states allow the determination of many A-state parameters with increased precision, several for the first time, including the spin-orbit splitting. The analysis confirms our earlier reinterpretation of older photoelectron spectroscopy data and allows the accurate prediction of the frequencies of strong infrared transitions between the X and A states, which have astrophysical significance.