Rayleigh scattered light

Figure 9.27 In Raman spectroscopy, light from a laser is shone at a sample. It is monochromated at a frequency of v0. Most of the light is transmitted. Most of the scattered light is scattered elastically, so its frequency remains at v0 this is Rayleigh scattered light. Raman scattered light has a frequency V(SCattered) = v0 — vibration) The sample is generally in solution...

The first term on the right-hand side of Equation (1.24) accounts for the generated intensity due to Rayleigh scattered light, while the second term is related to the intensity of the Raman scattered light. For visible light coo 10 Hz, while the characteristic phonon frequencies are much shorter, typically 12 10 Hz. Then coq and the intensity of Raman scattering varies as coq, as stated in point (iv) above. 

Fig. 6. Experimental arrangement for lifetime measurements by the phase-shift method, using laser excitation. The laser beam is amplitude-modulated by a Pockel cell with analysing Nicol prism and a small part of the beam is reflected by a beam splitter B into a water cell, causing Rayleigh scattering. This Rayleigh-scattered light and the fluorescence light from the absorption cell are both focused onto the multiplier cathode PMl, where the difference in their modulation phases is detected. (From Baumgartner, G., Demtroder, W., Stock, M., ref. 122)).

Rayleigh scattered light from dense transparent media with nonuniform density. If these nonuniformities are time-independent, there will be no frequency shift of the scattered light. If, however, time-dependent density fluctuations occur, as e. g. in fluids, due to thermal or mechanical processes, the frequency of the scattered light exhibits a spectrum characteristic of this time dependence. The type of information which can be obtained by determining the spectral line profile and frequency shift is described in an article by Mountain 235). 

The velocity, density and temperature of a streaming gas can be determined by measuring the magnitude, frequency and spectral distribution of Rayleigh-scattered light from two simultaneously pulsed ruby lasers with parallel beams and slightly different frequencies 246)... 

T. Bancewiez. Molecular-statistical theory of the influence of molecular fields in liquids on the spectral distribution and intensity of Rayleigh scattered light in the approach of Racah algebra. Acta Phys. Polonica, A, 56 431-438 (1979). 

B. J. Berne and R. Pecora. Light scattering as a probe of fast-reaction kinetics The depolarized spectrum of Rayleigh scattered light from a chemically reacting medium. J. Chem. Phys., 50 783-791 (1969) see also Erratum, J. Chem. Phys., 57 475-476 (1969). 

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