https://doi.org/10.1351/goldbook.08625
Raman scattering showing absorption when Stokes Raman scattering exceeds anti-Stokes Raman scattering, in an experiment in which a sample is simultaneously illuminated by coincident beams from a continuum source and a pulse laser at . Energy is absorbed from the continuum at where is the wavenumber of a Raman-active vibration in the sample that is excited by this process, and this energy is emitted at .