Collisional line-shape parameters and their temperature dependence for the ν1+ν3 band of C2H2 perturbed by CO2. (December 2017) - Esteki, K.
Abstract: CO2 -broadened line widths and CO2 -pressure induced line shifts have been measured for 42 R - and P -branch transitions in the ν1 +ν3 band of acetylene at seven temperatures in the range 216–333 K to obtain the temperature dependences of broadening and shift coefficients. The spectra were recorded by a 3-channel tunable diode laser spectrometer, and the traditional Voigt-profile model was employed to retrieve the line parameters with a multispectrum fitting procedure. The line-broadening and line-shifting coefficients as well as their temperature-dependence parameters have been also evaluated theoretically, in the frame of a semi-empirical approach based on analytical Anderson-type expressions and including a few-parameter correction to account for the real curved trajectories. Being validated by comparison with measurements, this approach has been used to compute extensive (0≤ J ≤70) R - and P -line lists which could be useful for atmospheric/astrophysical applications and spectroscopic databases. Highlights: Measurements of C2 H2 -CO2 line widths and shifts at various temperatures. Experimental determination of line-width and line-shift temperature dependences. Calculations of C2 H2 -CO2 line widths and shifts for large ranges of quantum numbers. Theoretical evaluation of temperature-dependence parameters for widths and shifts. Theoretical line-lists for collisional widths, shifts and their temperature dependences.