The diffuse reflectance spectra in the 0.3 to 2.1 micrometer wavelength region have been measured for several samples of clay minerals sometimes found in the atmospheric aerosol. Examples of spectra are shown for different hydration states of several montmorillonite and kaolin group minerals. It was found that these clays show absorption features in the wavelength regions where liquid water absorbs. These absorption bands are removed by dehydration, as would be expected. It is concluded that the major features of the near infrared absorption spectra of montmorillonite and kaolin clays are determined primarily by the water present in the clay structures. In addition, the spectra show evidence of strong absorption in the near ultraviolet and short wavelength visible region. This latter absorption is a general feature of all the clay samples investigated.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not have access to this content, please speak to your institutional administrator if you feel you should have access.