Rayleigh-Brillouin light scattering spectroscopy of nitrous oxide (N${}_2$O)

Abstract

High signal-to-noise and high-resolution light scattering spectra are measured for nitrous oxide (N${}_2$O) gas at an incident wavelength of 403.00 nm, at 90${}^{\circ }$ scattering, at room temperature and at gas pressures in the range $0.5-4$ bar. The resulting Rayleigh-Brillouin light scattering spectra are compared to a number of models describing in an approximate manner the collisional dynamics and energy transfer in this gaseous medium of this polyatomic molecular species. The Tenti-S6 model, based on macroscopic gas transport coefficients, reproduces the scattering profiles in the entire pressure range at less than 2\% deviation at a similar level as does the alternative kinetic Grad's 6-moment model, which is based on the internal collisional relaxation as a decisive parameter. A hydrodynamic model fails to reproduce experimental spectra for the low pressures of 0.5-1 bar, but yields very good agreement ($<1$\%) in the pressure range $2-4$ bar. While these three models have a different physical basis the internal molecular relaxation derived can for all three be described in terms of a bulk viscosity of ${\eta }_b\sim (6\pm 2)\times 10^{-5}$ Pa$\cdot$s. A 'rough-sphere' model, previously shown to be effective to describe light scattering in SF${}_6$ gas, is not found to be suitable, likely in view of the non-sphericity and asymmetry of the N-N-O structured linear polyatomic molecule.

References in corpus (5)

• A systematic study of Rayleigh-Brillouin scattering in air, N2 and O2 gases
• Temperature-dependent bulk viscosity of nitrogen gas determined from spontaneous Rayleigh-Brillouin scattering
• A Rayleigh-Brillouin scattering spectrometer for ultraviolet wavelengths
• Rayleigh-Brillouin scattering of carbon dioxide
• Rayleigh-Brillouin scattering in SF${}_6$ in the kinetic regime

Cited by in corpus (4)

• Bulk viscosity of CO${}_2$ from Rayleigh-Brillouin lightscattering spectroscopy at 532 nm
• Extraction of the translational Eucken factor from light scattering by molecular gas
• Rayleigh-Brillouin light scattering spectroscopy of air; experiment, predictive model and dimensionless scaling
• Rayleigh-Brillouin scattering in binary mixtures of disparate-mass constituents: SF${}_6-$He, SF${}_6-$D${}_2$ and SF${}_6-$H${}_2$