Experimental line parameters of the b1 Sigma(g)+ <-- X3 Sigma(g)- band of oxygen isotopologues at 760 nm using frequency-stabilized cavity ring-down spectroscopy.
Positions, intensities, self-broadened widths, and collisional narrowing coefficients of the oxygen isotopologues 16O18O, 16O17O, 17O18O, and 18O18O have been measured for the b1 Sigma(g) + <-- X3 Sigma(g) - (0,0) band using frequency-stabilized cavity ring-down spectroscopy. Line positions of 156 P-branch transitions were referenced against the hyperfine components of the 39K D1 (4s 2S1/2 --> 4p 2P1/2) and D2 (4s 2S1/2 --> 4p 2P3/2) transitions, yielding precisions of approximately 0.00005 cm-1 and absolute accuracies of 0.00030 cm-1 or better. New excited b1 Sigma(g) + state molecular constants are reported for all four isotopologues. The measured line intensities of the 16O18O isotopologue are within 2% of the values currently assumed in molecular databases. However, the line intensities of the 16O17O isotopologue show a systematic, J-dependent offset between our results and the databases. Self-broadening half-widths for the various isotopologues are internally consistent to within 2%. This is the first comprehensive study of the line intensities and shapes for the 17O18O or 18O2 isotopologues of the b1Sigma(g) + <-- X3 Sigma(g) - (0,0) band of O2. The 16O2, 16O18O, and 16O17O line parameters for the oxygen A-band have been extensively revised in the HITRAN 2008 database using results from the present study.
Robichaud
David J
DJ
Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Yeung
Laurence Y
LY
Long
David A
DA
Okumura
Mitchio
M
Havey
Daniel K
DK
Hodges
Joseph T
JT
Miller
Charles E
CE
Brown
Linda R
LR