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The structure of an iron oxide cluster incorporated into zeolite Y, determined by HRTEM and SAED

  • A. Carlsson
  • G. Karlsson
  • J.-O. Bovin
  • T. Oku
  • Y. Okamoto
  • N. Ohnishi
  • O. Terasaki
Conference paper

Abstract

The atom positions of an iron cluster (Fe6O n ) inside the framework of a zeolite (FAU, Na48(Fe2O3)38Al48Si144O384) were determined through the use of electron crystallography methods for three-dimensional reconstruction of atomic positions within the cluster from high-resolution electron micrographs and selected-area electron diffraction. The iron-containing FAU structure was determined in the space group Fd3m (a = 24.7 Å) by the use of 42 unique reflections. The Fe6O n molecule is situated in the sodalite cage with the iron atoms facing the square windows of the cage. The iron-iron distance is 3.6 Å and the distances between iron atoms and the nearest oxygen atoms in the sodalite cage are close to 2.2 Å. As a verification of the method, the same technique was used for the dermination of the structure of Na48Al48Si144O384 without iron, and the Si/Al atom positions of the zeolite framework were found to coincide with those determined from single crystal X-ray diffraction methods.

PACS

61.14.-x Electron diffraction and scattering 61.14.Rq Other electron diffraction and scattering techniques for structure analysis 61.46.+w Clusters, nanoparticles, and nariocrystalline materials 

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Copyright information

© Springer-Verlag Italia 1999

Authors and Affiliations

  • A. Carlsson
    • 1
  • G. Karlsson
    • 2
  • J.-O. Bovin
    • 1
  • T. Oku
    • 1
  • Y. Okamoto
    • 3
  • N. Ohnishi
    • 4
  • O. Terasaki
    • 5
    • 6
  1. 1.National Center for HREM, Inorganic Chemistry 2, Chemical CenterLund UniversityLundSweden
  2. 2.Biomicroscopy Unit, Inorganic Chemistry 2, Chemical CenterLund UniversityLundSweden
  3. 3.Department of Material ScienceShimane UniversityMatsue 690Japan
  4. 4.Institute for Materials ResearchTohoku UniversitySendaiJapan
  5. 5.Microstructure Physics Group, Department of Physics, Graduate School of Science, and Center for Interdisciplinary ResearchTohoku UniversitySendaiJapan
  6. 6.CRESTJapan Science and Technology Corporation (IST)Japan

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