Progress Toward a Better Understanding of Signal Generation Processes in the Laser‐ExcitedPhotothermal Spectroscopy of Homogeneous Samples

Document Type

Article

Journal/Book Title

Trends in Analytical Chemistry

Publication Date

1998

Volume

17

First Page

520

Last Page

532

Abstract

This article examines some recent experiments and theories that have advanced our understanding of the physical effects following thermal relaxation of the excited state. Experiments which show that the temperature-dependent refractive index is composed of density and pure-thermal terms are discussed. The importance of the purely thermal term is that it allows ultra-fast pulsed excitation sources to be used in photothermal refraction spectroscopy. This opens up new areas of applications in ultra-fast measurement. The effect of and progress towards the elucidation of specific volume changes are reviewed. Finally, recent progress in understanding nonlinear optical absorption and its effect on the photothermal signal are summarized.

Link to Full Text

Share

COinS