Difference-frequency source for very low optical frequencies spectroscopy: CO2 induced spectra

On the nature of sub-THz continuum absorption in CO2 gas, its mixture with Ar, and in pure water vapor

“…The experimental data from the literature [49][50][51][52][53][54][55][56][57][58] and the results of calculations of bimolecular absorption by the CTS method 16,18,20 are presented in Fig. 1 and 2 for comparison.…”

“…1 and 2 for comparison. 20 (gray symbols), experimental data 49,[52][53][54][56][57][58][59][60] (green symbols), approximation of new experimental data by function (4) (red solid curve) together with the total uncertainty of the approximation (red dashed curves), result of calculation of bimolecular absorption (free pairs, stable and metastable dimers) 18 green solid curve, the result of calculating absorption by free molecular pairs and metastable dimers 18 4) (red solid curve) together with the complete uncertainty of the approximation (red dashed curves); experimental data [49][50][51] (bright green symbols); calculated bimolecular absorption 18 for free pairs (green dotted curve), free pairs and metastable dimers (green dashed curve), free pairs, stable and metastable dimers (solid green curve); calculated bimolecular absorption (free pairs, stable and metastable dimers) 16 (blue solid curve). Red vertical bars are the CO 2 -Ar rigid rotor spectrum stick-diagram (see text for details).…”

“…Fig.1Spectral function of the CO 2 -CO 2 continuum at 297 K: new experimental data (black symbols), experimental data 20 (gray symbols), experimental data49,[52][53][54][56][57][58][59][60] (green symbols), approximation of new experimental data by function (4) (red solid curve) together with the total uncertainty of the approximation (red dashed curves), result of calculation of bimolecular absorption (free pairs, stable and metastable dimers)18 green solid curve, the result of calculating absorption by free molecular pairs and metastable dimers18 (green dashed curve), the result of calculating absorption by free molecular pairs only (green dotted line). Red vertical bars are the CO 2 -CO 2 rigid rotor spectrum stick-diagram (see text for details).…”