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Infrared Absorption Spectra of Non-Spherical Particles Treated in the Rayleigh-Ellipsoid Approximation

  • Donald R. Huffman
  • Craig F. Bohren

Abstract

A comparison of small particle extinction spectra calculated for spheres with extinction measurements shows the inadequacy of the spherical approximation in treating strong infrared absorption bands. A simple expression for absorption cross sections of non-spherical particles is derived by integrating over a distribution of shape parameters in the Rayleigh-ellipsoid approximation. For comparison with the theoretical results infrared extinction measurements were made of sub-micron quartz particles dispersed in a KBr matrix. The favorable comparison of theory and experiment suggests that the treatment of shape effects in infrared absorption spectra by means of a distribution of ellipsoids constitutes a major improvement.

Keywords

Absorption Cross Section Shape Effect Infrared Absorption Spectrum Ellipsoidal Shape Quartz Particle 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Donald R. Huffman
    • 1
  • Craig F. Bohren
    • 2
  1. 1.Dept. of PhysicsUniv. of ArizonaTucsonUSA
  2. 2.Institute of Atmospheric PhysicsUniv. of ArizonaTucsonUSA

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