Photoacoustic spectroscopic studies on a mixture of six CO2 isotopes (12C16O2, 12C18O2, 13C16O2, 13C18O2, 16O12C18O, and 16O13C18O) in the wavelength range of 9–11 µm by use of a home-built high-pressure continuously tunable CO2 laser with a bandwidth of 0.017 cm-1 are discussed. The concentrations of all CO2 isotopes present in the mixture could be determined with good accuracy. Furthermore, the previously unknown absorption cross sections of some important lines of the 12C18O2, 13C18O2, and 16O13C18O isotopes in the 9–11-µm range are reported.
© 1997 Optical Society of America
Original Manuscript: August 22, 1996
Revised Manuscript: December 4, 1996
Published: May 20, 1997
I. G. Calasso, V. Funtov, and M. W. Sigrist, "Analysis of isotopic CO2 mixtures by laser photoacoustic spectroscopy," Appl. Opt. 36, 3212-3216 (1997)