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The Determination of (Si,Al) Distribution in Zeolites

  • Alberto Alberti
  • Glauco Gottardi
  • Tiziana Lai
Part of the NATO ASI Series book series (NSSB, volume 221)

Abstract

The effects of the:
  1. 1.

    variation of the Si-O and Al-O distances depending on bonding forces on T and O atoms

     
  2. 2.

    variation of the measured T-O distances depending on disorder in the (Si,Al) distribution

     
  3. 3.

    variation of the measured T-O distances depending on the temperature of the diffraction data collection

     
  4. 4.

    shortening of the measured T-O distances as a result of averaging when apparent symmetry is higher than true symmetry

     
on the determination of the Al-content in the tetrahedral sites of zeolites has been shown. All these effects have a remarkable influence on the calculated Al-fraction. The differences in the (Si,Al) distribution found by comparing the results of a method proposed by Alberti and Gottardi1, which takes into account effects no. 1 and no. 2, and of Jones’2 determinative curve are stressed.

Keywords

Neutron Diffraction Thermal Motion Tetrahedral Site Bonding Force Acentric Domain 
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 1990

Authors and Affiliations

  • Alberto Alberti
    • 1
  • Glauco Gottardi
    • 2
  • Tiziana Lai
    • 1
  1. 1.Istituto Geologico MineralogicoUniversità di SassariItaly
  2. 2.Istituto di MineralogiaUniversità di ModenaItaly

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