Light scattering Rayleigh equation

The electron clouds of a molecule irradiated with visible light will orient themselves to some extent in line with the electric vector of the light. If the light is plane polarised, scattered light is visible only in one plane, and if the dimensions of the molecule are small compared with the wavelength of the light, the Rayleigh equation, eqn. (4.21), holds ... 

The Rayleigh ratio as defined by Equation (24) has a precise meaning, yet it is a quantity somewhat difficult to visualize physically. After we have discussed the experimental aspects of light scattering, we shall see that Re is directly proportional to the turbidity of the solution when turbidity is the same as the absorbance determined spectrophotometrically. 

N. When this is combined with the light scattering equation of Rayleigh, and allowance made for a distribution in the particle size because of the stochastic nature of the process, one obtains (37)... 

Small Particles—The optical properties of suspended particles depend on a number of variables. In his important contributions on the color of the sky, Rayleigh (1871) set forth the equation governing the intensity of light scattered by small spherical particles of uniform size in a gaseous medium. This equation for a single particle is as follows ... 

Light scattered by small particles will be completely polarized if they are optically isotropic and distributed entirely at random. This polarization will take place in any plane normal to the scattered rays. In practice complete polarization by a suspension of particles is never realized, and consequently suitable corrections must be applied to Rayleigh s equation to account for the shape of the particles. 

Equation (7.36) is known as the Debye plot. Figure 7.11a and Figure 7.11b show the excess Rayleigh scattering intensities of polyacrylamide from MALLSP (multi angle laser light scattering photometer) and LALLSP, respectively. 

Equation (6.12) is important it shows that we can determine the relative molar mass of the molecule from the experimental measurement of the Rayleigh ratio in light scattering. 

Equations (14) and (15) are different forms of the Rayleigh expression for light scattering from small particles if excited... 

In agreement with the Rayleigh equation, the scattering of light by homogeneous systems, such as pure liquids and true solutions, should be very small due to a small size of scattering centers. In reality, however, there is a... 

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