Diode-laser measurements of He- and N2-broadening coefficients and line-mixing effects in the Q-branch of the ν1-ν2 band of CO2

He- and N-2-broadening coefficients have been measured for the lines Q2 to Q22 of the v(1)-v(2) (10(0)01 <-- 01(1)01) band of CO2 near 720.80 cm(-1), using a tunable diode-laser spectrometer. The collisional widths have been obtained at low perturber pressures by fitting Voigt and Galatry profiles to the measured shapes of the lines. Spectra in the v(1)-v(2) band of CO2 in mixture with He and N-2 have also been recorded at higher pressures. The deviations observed from an additive superposition of Lorentzian lines have been notably reduced by considering collision-induced line-mixing effects. (C) 1998 Elsevier Science Ltd. All rights reserved.