Rayleigh scattering revisited: From gases to crystals

The intensity of Rayleigh scattering is proportional to the number of scatterers in a dilute gas. In contrast, for liquids or solids at low temperatures, any lateral Rayleigh scattering can be suppressed significantly. Microscopically, it is not obvious why the lateral Rayleigh scattering is diminished as the density in the medium increases. We use simple exactly solvable models to show that the suppression of Rayleigh scattering is proportional to the ratio of the interparticle correlation length to the interparticle distance. The wavelength of the scattered radiation is much larger than both these quantities in many cases of interest and does not play an explicit role in the suppression of lateral Rayleigh scattering.