Determination of the line-shift and line-broadening coefficients in the nu(3) band of NO2 perturbed by O-2, N-2, H-2, D-2, and CO2

A high-resolution three-channel diode-laser spectrometer was used to record a large number of spectra with (NO2)-N-14-O-16, and foreign gas pressures ranging from 0.1 to 0.4 and 20 to 150 Torr, respectively, at room temperatu re. The 6.2-mu m region corresponding to the v(3) band of NO2 was analyzed and the broadening and shift coefficients were derived in the case of colli sions between NO2 and H-2, D-2, O-2, N-2, CO2, and SO2 for 13 lines with 18 less than or equal to N(n)less than or equal to 38 and 1 less than or equa l to K(a)(n)less than or equal to 5. This experimental study confirms gener al trends. The broadening coefficients decrease with an increase of the rot ational quantum number N-n whereas the absolute values of the line-shift co efficient increase with increasing N-n. In the case of the studied diatomic perturbers the size of the broadening coefficients corresponds to the size of the quadrupole moments. The only collision partner with nonvanishing di pole moment, SO2, shows the largest broadening effect as expected. All shif t coefficients are negative for the Lines under study. (C) 1999 Academic Pr ess.