Pressure broadening coefficients and line strength parameters of D2O vapour were measured with tunable diode laser absorption spectrometer for (010)-(000) band around 8.3 μm wavelength region. The D2O vapour is produced by passing Ar (>99.999%) through bubbler containing liquid phase sample and it cooled down in the molecular supersonic jet. Lead-salt diode laser source mounted in a liquid-nitrogen cooled Dewar (L5736, laser components) is used to probe the fundamental band transition of D2O vapour in the center of multipass cell of about 96 passes of the laser beam. In irregular steps temperature was changed to shift the laser’s emission wavelength modal. The results of the fitting at 1194.66 cm-1 are presented; the experimental profiles in the same scale for three different pressures are plotted. We used a lock-in detection technique and phase sensitive detection method to get second derivative signal, then Voigt profile is used for fitting and extraction of line-broadening coefficients. Line positions and pressure-broadening coefficients of 6 lines are determined.
A.A. Mahmoud, R. Zheng, C.X. Duan and G.M. Huang, 2009. Line-Shape Study of Deuterated Isotopomer of H2O by Tunable Diode Laser Spectrometer Around 8.3 μm Wavelength Region. Journal of Applied Sciences, 9: 2852-2856.