Line Shift Investigations for Different Isotopomers of Carbon Monoxide.

Line shift coefficients for five lines of five different isotopomers in the fundamental band of CO in the spectral region near 2058 cm-1 were measured using a three channel lead salt diode laser spectrometer. The study includes the lines P(3) of 13C17O, R(3) of 13C18O, P(9) of 12C18O, P(10) of 13C16O, and P(21) of 12C16O, and covers collisions with N2, O2, H2, D2, He, Ne, Ar, Kr, and Xe. Line shifts of the isotopomers 13C16O, 12C18O, 13C18O, and 13C17O were determined for the first time. Within the experimental uncertainty no significant dependence of the shift effect on the isotopomer was found. The R-branch line under study shows a smaller line shift coefficient than a P-branch line with a similar rotational quantum number. With increasing mass of the noble gas perturber the absolute size of the shift coefficient increases. Moreover self- and nitrogen-broadening coefficients for the isotopomer lines were determined. Compared to previous measurements no significant deviations between different isotopomers were observed. Copyright 1998 Academic Press.