The photo
bleaching of a feature, normally a narrow range, within an inhomogeneous broader absorption
or emission band. The holes are produced by the disappearance of resonantly excited
molecules as a result of photophysical or photochemical processes. The resulting spectroscopic
technique is site-selection
spectroscopy.
Source:
PAC, 1996, 68, 2223
(Glossary of terms used in photochemistry (IUPAC Recommendations 1996))
on page 2246