Temperature Dependence of Pressure Broadened Linewidth of J = 1 ⇐ 0 Rotational Transition of CH₃C₁₄N Molecule Mixed with OCS and H₂Molecule

Abstract

The temperature dependence of the pressure-broadening parameters of the J = 1 O rotational transition of OCS and H2 in the ground vibrational state of CH3C 14 N molecule is measured in the temperature range between 248 and 293 K. The line shape of the absorption is recorded with a Stark modulated microwave spectrometer. Using least squares fits of the data to the Voigt line function, several contributions to the linewidth have been deduced. The experimental results are compared with the calculated results using Murphy and Boggs collision broadening theory. The pressure-broadening parameters CW (x) of the gas mixture CH3CN+OCS and CH3CN-+H2 are 14.05f 0.30 MHz/Tr, 9.15f 0.12 MHz/Tr, respectively and the temperature dependence parameters a are -0.90 ± 0.07 and -0.77 ± 0.08.