holder

The following is an abstract for the selected article. A PDF download of the full text of this article is available here. Members may download full texts at no charge. Non-members may be charged a small fee for certain articles.


Studies of Multichannel Photothermal Refraction for the Measurement of Absolute Absorptivity

Volume 46, Number 10 (Oct. 1992) Page 1583-1586

Klatt, Leon N.


Multichannel crossed-beam photothermal refraction experiments have been performed. Iron(II)-phenanthroline in methanol was the test solute. The response as a function of concentration exhibited a nonlinear relationship, which does not agree with the current theoretical description of the phenomena. Although photophysical and photochemical processes were not totally eliminated as possible causes of the nonlinear concentration response, arguments are presented which indicate, for the experimental conditions employed in this study, that these processes are negligible. It is proposed that the heat transfer model must be modified to include refractive index gradients in both the radial and axial coordinates of the pump laser beam.