Temperature dependences of self- and N-2-broadened line-shape parameters in the nu(3) and nu(5) bands of (CH3D)-C-12: Measurements and calculations

This paper presents the results of a spectroscopic line shape study of self- and nitrogen-broadened (CH3D)-C-12 transitions in the nu(3) and nu(5) bands in the Triad region. We combined five pure gas spectra with eighteen spectra of lean mixtures of (CH3D)-C-12 and nitrogen, all recorded with a Bruker IFS-125 HR Fourier transform spectrometer. The spectra have been analyzed simultaneously using a multispectrum nonlinear least squares fitting technique. N-2-broadened line parameters for 184 transitions in the nu(3) band and 205 transitions in the nu(5) band were measured. In addition, line positions and line intensities were measured for 168 transitions in the nu(3) band and 214 transitions in the nu(5) band. We have observed 10 instances of weak line mixing corresponding to K `' = 3 A1 or A2 transitions. Comparisons were made for the N-2-broadening coefficients and associated temperature exponents with corresponding values calculated using a semi-classical Robert Bonamy type formalism that involved an inter-molecular potential with terms corresponding to short- and long-range interactions, and exact classical molecular trajectories. The theoretical N-2-broadened coefficients are overestimated for high J values, but are in good agreement with the experimental values for small and middle range J values. (C) 2016 Elsevier Ltd. All rights reserved.