Light Scattering Rayleigh factor

Kaye W, McDaniel JB (1974) Low-angle laser light scattering - Rayleigh factors and depolarization ratios Appl Opt 13 1934-1937... 

Rayleigh s results do not apply fully to solutions. He had assumed that each particle acted as a point source independent of all others, which is equivalent to assuming that the relative positions of the particles are random. This is true in the gases with which he worked, but is not true in liquids. Hence, for solutions, the scattered light is less intense by a factor of about 50 due to interference of the light scattering from different particles. 

A simple way to determine the relationship between molecular weight and intensity of scattered light is to recast Equation (4.4) by defining an optical constant K using Equation (4.5) and Ro, the Rayleigh factor (Equation (4.6)). 

According to the fluctuation theory of light scattering (Flory 1953), the relationship between the Rayleigh factor and the physical characteristics of the macromolecules in solution is expressed in the following general form ... 

The correction of absorption depends on the geometry of the cell and the scattering volume. Different relationships have been proposed to correct the Rayleigh factor measured with conventional goniometers, in which the detector rotates around the sample m a horizontal plane (Brice et al. 1953, Forss et al. 1967, Pla et al. 1977). With LALLS (low angle laser light scattering) pho-... 

Conventionally, the excess light scattered per unit volume at angle 6 from the transmitted beam, e, is reported as a Rayleigh factor (or ratio). 

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