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.


Aggregation and Matrix Effects on the Infrared Spectrum of Microcrystalline Powders

Volume 44, Number 3 (April 1990) Page 418-426

Iglesias, J.E.; Ocaña, M.; Serna, C.J.


Two pure phonon theories have been used for the interpretation of the infrared absorption spectra of powdered solids: the theory of absorption and scattering of light by small particles (TAS) and the theory of the average dielectric constant (TADC). The comparison between both theories shows that they are equivalent for particle sizes smaller than 2 μm and low particle concentration. However, when the particle concentration is significant, only TADC can be used to analyze the experimental spectra, thus obtaining a qualitative estimation of particle aggregation in a powder. Matrix effects were also observed in the experimental powder spectra, which can be accounted for by TADC.