Raman effect

Raman effect

In the Raman effect, part of the original photon energy is used to excite a resonant vibration – usually described as a three-level event via a virtual excited state.

The Raman effect, in spectroscopy, is the change in the wavelength of light that occurs when light scatters inelastically (see scattering) from atoms or molecules. It arises from radiation exciting (or de-exciting) atoms or molecules from their initial states. The Raman effect is named after the Indian physicist Chandrasekhar Raman, who won a Nobel Prize in 1930 for his discovery.