Recommended isolated-line profile for representing high-resolution spectroscopic transitions

Published

September 11, 2014

Author(s)

Joseph T. Hodges, Jonathan Tennyson, P F. Bernath, Alain Campargue, A Csaszar, L Daumont, R R. Gamache, D Lisak, Olga Naumenko, Lawrence Rothman, Ha Tran, N Zobov, Boone Chris, L Gianfrani, Jean M. Hartmann

Abstract

Recommendations of an IUPAC Task Group formed in 2011 on “Intensities and line shapes in high-resolution spectra of water isotopologues from Experiment and Theory" (Project No. 2011-022-2- 100) on line profiles of high-resolution rotational-vibrational isolated transitions perturbed by gas phase neutral molecules are presented. The well-documented inadequacies of the Voigt profile, used almost universally by databases and radiative transfer codes, to represent the effects of pressure and Doppler broadening on the vibrational-rotational and pure rotational isolated transitions of water have resulted in the development of a variety of alternative line profile models. These models capture more of the physics involved in the influence of pressure on the line- shape but, in general, at the price of greater complexity. The Task Group recommends that the partially-Correlated quadratic-Speed-Dependent Hard-Collision profile should be adopted as the appropriate model of high-resolution spectroscopy moving beyond the Voigt profile. For simplicity this should be called the Hartmann-Tran profile (HTP). This profile is sophisticated enough to capture the various collisional contributions to the isolated line shape, can be computed in a straightforward and rapid manner, and reduces to simpler profiles, including the Voigt profile, under certain simplifying assumptions.

Citation

Pure and Applied Chemistry

Pub Type

Journals

Download Paper

https://doi.org/10.1515/pac-2014-0208

Keywords

water, line profile, absorption spectroscopy, Voigt profile

Citation

Hodges, J. , Tennyson, J. , Bernath, P. , Campargue, A. , Csaszar, A. , Daumont, L. , Gamache, R. , Lisak, D. , Naumenko, O. , Rothman, L. , Tran, H. , Zobov, N. , Chris, B. , Gianfrani, L. and Hartmann, J. (2014), Recommended isolated-line profile for representing high-resolution spectroscopic transitions, Pure and Applied Chemistry, [online], https://doi.org/10.1515/pac-2014-0208 (Accessed December 13, 2024)