Lead-salt-diode lasers have been used to detect more than 100 absorption lines of H3O+ in an ac discharge by using the velocity-modulation technique. Many lines have been assigned to vibration-rotation transitions in the 1− ← 0+ and 1+ ← 0− components of the ν2 inversion mode of H3O+ with band centers at 954.4 and 525.8 cm−1, respectively. The results for the former band extend those of earlier work and lead to some minor changes in assignment.
© 1985 Optical Society of America
P. B. Davies, P. A. Hamilton, and S. A. Johnson, "Infrared laser spectroscopy of H3O+ between 510 and 1150 cm−1," J. Opt. Soc. Am. B 2, 794-799 (1985)