Collisional broadening of vibrational-rotational CO<sub>2</sub> lines by buffer gases
Unsaturated absorption coefficients in pure CO<sub>2</sub> and binary mixtures of CO<sub>2</sub> with buffer gases M <sub>j</sub> (He, Ar, Kr, Xe, N<sub>2</sub>, O<sub>2</sub>, CO, N<sub>2</sub>O, <sup>13</sup>C<sup>16</sup>O<sub>2</sub>) were measured at the central frequencies of the R (8), R (22), R (34), P (8), P (22), and P (36) CO<sub>2</sub> spectral lines of the 10<sup>0</sup>0-00<sup>0</sup>1 transition at 300-700 K with a tunable CO<sub>2</sub> laser. A technique is described and the coefficients of self-broadening and broadening of CO<sub>2</sub> spectral lines by a buffer gas M <sub>j</sub> are calculated. It is shown that the efficiency of CO<sub>2</sub> 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 CO<sub>2</sub> spectral lines can be highly accurate approximated by power functions with two different exponents.