A new hydrochloric acid 2-0 band analysis: Two temperature study

Abstract

A new study of the 2−0 band of the hydrochloric acid molecule is performed by high resolution Fourier-transform absorption spectroscopy in the near infrared region. The spectra were measured at two different temperatures, 293 K and 315 K, for different pressures at each temperature. The spectral linewidths were analysed in a two-step procedure, being first performed by directly measuring the linewidth and second by fitting each spectral line to a model line profile, using Gaussian, Loretzian and Voigt profiles. A study of the profiles that best describe the spectral line fits is carried out in this work. The behavior of the spectral lines self-broadening and their corresponding self-induced shifts were studied for different values of rotational quantum numbers. The analysis are performed for both isotopes of the molecule and the self-broadening and self-shift coefficients are presented.