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)


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.


Neutron Diffraction Thermal Motion Tetrahedral Site Bonding Force Acentric Domain 
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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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