Classical/ Static/ Multi-Angle Light Scattering




In the 19th century Lord Rayleigh (John William Strutt) offered the first explanation for the sky's blue color (on a clear day!). From Rayleigh's initial theory representing a simplification of Maxwell's electromagnetic theory for the case of particles very small compared to the wavelength of the incident light, the theory was extended to describe the scattering of light by larger macromolecules in solution. This is called the Rayleigh-Gans-Debye (RGD) theory of light scattering to recognize the roles of the various scientists involved in its development.

In a typical Rayleigh scattering experiment, a well collimated, single frequency polarized light beam (e.g. from a laser) is used to illuminate a solution containing a suspension of the macromolecules of interest. The electric field of the polarized light beam is generally produced perpendicular to the plane in which the intensity and angular dependence of the subsequently scattered light is to be measured. The intensity carries information about the molar mass, while the angular dependence carries information about the size of the macromolecule.

The following theory section contains a brief overview of the following topics related to Rayleigh scattering: