Absolute differential Raman scattering cross section of nitrogen

Absolute Differential Raman Scattering Cross Section of Nitrogen 

The absolute differential scattering cross section of the standard needs to be determined as precisely as possible. A number of measurements has been performed ovm-the past forty years [260,278-287]. The introduction of lasers in Raman spectroscopy and of computer processing of spectral data has improved highly the accuracy of Raman intensity measurements. As a result, the absolute differential Raman scattering cross section of nitrogen reported frrom different laboratories deviates within a few percent only [260,284,285,287]. 

One of the possible approaches in determining (da/dn)Q is to use the absolute differential cross section of the strongest purely rotational Raman line J = 1- 3 (J the rotational quantum number) of hydrogen at 587 cm l as a standard. It is given by [260] 

Yo is the anisotropy at the equilibrium geometry. The rectangular experimental setup, as shown in Fig. 8.1, is considered. Both experiment and theory have provided a reliable value for the hydrogen anisotropy. Moreover, its dependence on the excitation wavelength has been thoroughly established. As a result, the absolute differential cross section of flie hydrogen rotational line (do/dn)jot,H2 accurately determined. The estimated value has been employed in determining the absolute differential cross 

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A. Absolute Differential Raman Scattering Cross Section of Nitrogen.212... 

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See also in sourсe #XX -- [ ]

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