Collisional Broadening of Spectral Lines in the X --> b System of O2 and theFirst Vibrational Band of NO by the Noble Gases

摘要

Collisional broadening of the rotational spectral lines of the X to b system ofO2 and the first vibrational band of NO by the noble gases is examined by Fourier transform spectroscopy. Peaks of the individual rotational lines are modeled with a Voigt function, from which Lorentzian half widths are extracted. Lorentzian widths are plotted vs. pressure of foreign gas, from which the pressure broadening coefficients and pressure broadening cross sections are calculated. The pressure broadening coefficients are compared to theoretical values determined by past research for O2. NO coefficients are compared to similar research using N2 as collision partner. O2 broadening coefficients/cross sections were found to increase with decreasing rotational quantum number. Also, a linear dependence is found between cross section and both polarizability of the collision partner and reduced mass of the collision pair.