Photothermal spectroscopy and its analytical application

Summary Photothermal spectroscopy relies on the detection of thermal or acoustic waves generated by the absorption of optical radiation and subsequent radiationless deexcitation. With this technique the absorbed energy is detected directly. Hence, weakly absorbing, opaque and scattering samples can be readily addressed with this spectroscopy. Various photothermal and photoacoustic detection schemes and the underlying physical principles are discussed. The potential and the limitations of this technique are highlighted with typical analytical applications.