Collisional broadening of vibrational-rotational CO<sub>2</sub> lines by buffer gases
Unsaturated absorption coefficients in pure CO2 and binary mixtures of CO2 with buffer gases M j (He, Ar, Kr, Xe, N2, O2, CO, N2O, 13C16O2) were measured at the central frequencies of the R (8), R (22), R (34), P (8), P (22), and P (36) CO2 spectral lines of the 1000-0001 transition at 300-700 K with a tunable CO2 laser. A technique is described and the coefficients of self-broadening and broadening of CO2 spectral lines by a buffer gas M j are calculated. It is shown that the efficiency of CO2 interaction with diatomic and triatomic molecules is determined by the electric moment; in the case of inert gases, the mass factor plays the major role. It is ascertained that the temperature dependences of the collisional broadening of CO2 spectral lines can be highly accurate approximated by power functions with two different exponents.