Publications Details
High-Resolution Raman Measurements of Gradients at Interfaces
Harmon, Robert A.; Barlow, R.S.
Fundamental investigations of non-equilibrium gas-liquid interfaces at elevated pressure will require knowledge of gas-phase boundary conditions affecting the interface structure. To assess the feasibility of applying one-dimensional imaging of spontaneous Raman scattering to resolve species and temperature gradients in the gas-phase boundary layer above a fluoroketone liquid surface, spectra of fluoroketone (1,1,1,2,2,4,5,5,5-nonafluoro-4-(trifluoromethyl)-3-pentanone) vapor in a carrier gas (N2 or CO2) are reported over the temperature range 300 K to 700 K. The measured Raman spectra show no detectable broadband interference from laser-induced fluorescence. Features of the fluoroketone Raman spectrum overlap the CO2 spectrum, such that crosstalk corrections will be necessary for quantitative concentration measurements of CO2 in mixtures. High-resolution Raman spectra in this overlap region, acquired over the same temperature range, will enable future development of temperature dependent spectral libraries for fluoroketone.