Photon Correlation Spectroscopy

**Semantic type:** Laboratory Procedure

**Definition:** A type of spectroscopy that utilizes a laser beam to irradiate a sample containing particles in suspension, resulting in light scattering. Rapid fluctuations in scattering intensity, around a mean value at a certain angle, occur because of particle diffusion and are dependent upon on particle size. The calculated correlation function yields a diffusion coefficient, for a given temperature and viscosity, which can be used to calculate particle size.

**Synonyms:** - DLS - DYNAMIC LIGHT SCATTERING - Dynamic Light Scattering - PCS - Quasi-Elastic Light Scattering - Quasi-elastic Light Scattering