Raman scattering

Raman scattering is an inelastic scattering process that occurs when light interacts with molecular vibrations, phonons, or other low-frequency excitations in a material. This phenomenon is named after the Indian physicist C.V. Raman, who, along with his colleague, discovered it in 1928. In simple terms, when a monochromatic light source, typically a laser, shines on a sample, most of the light is elastically scattered, meaning it retains its original energy (or wavelength).