Strengths, Widths, and Shapes of the Lines of the 3ν CO Band

Abstract

Spectral curves of several CO samples have been used to investigate the 3ν band whose center is near 6350 cm−1. The strength of the band for the common 12C16O isotope has been found to be 0.0130±0.0005 atm−1·cm−1STP·cm−1. An empirical equation, Fm=1+0.011m, has been derived to account for the influence of vibration—rotation on line strengths. The half-widths of the self-broadened lines at 1 atm pressure vary from approximately 0.090 cm−1 at | m | = 1 to 0.062 cm−1 at | m | = 20. The widths of self-broadened lines are 1.08±0.005 times as great as N2-broadened lines at the same pressure. The Lorentz line shape appears to be appropriate for the collision-broadened lines within a few cm−1 of their centers; but the extreme wings of the lines are sub-Lorentzian.