Stokes Shift

Stokes Shift is the difference in wavelength (or color) between the light a substance absorbs and the light it emits. When a molecule absorbs light, it gets excited to a higher energy state. As it relaxes back to a lower energy state, it releases light—this emitted light is usually at a longer wavelength (lower energy) than the absorbed light. This shift helps scientists identify materials and understand their properties, as it indicates how much energy is lost during the process. Essentially, Stokes Shift is a measure of the energy difference between absorption and emission in fluorescent materials.