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Updated: Aug 10, 2026
11:32
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
Refinement of the structure of beta-U4O9
1Chemical Crystallography, University of Oxford, Chemical Research Building, Mansfield Road, OX1 3TA, England.
Summary
Beta-uranium oxide (Beta-U4O9) exhibits a superlattice structure derived from the fluorite arrangement of uranium dioxide (UO2). Additional oxygen atoms are located in specific clusters within this structure, refined using neutron diffraction data.
Area of Science:
- Solid-state chemistry
- Crystallography
- Materials science
Background:
- Beta-uranium oxide (Beta-U4O9) is a superlattice structure.
- It is based on the fluorite arrangement of uranium dioxide (UO2).
Purpose of the Study:
- To refine the crystal structure of Beta-U4O9.
- To understand the accommodation of additional oxygen atoms in the UO2-based structure.
Main Methods:
- Single-crystal neutron diffraction data was utilized.
- Structure refinement was performed following established procedures.
Main Results:
- The U atoms are positioned similarly to those in UO2.
- Additional O atoms occupy cuboctahedral clusters with 43m symmetry.
- These clusters are centered on 12-fold sites within the I43d cubic space group.
Conclusions:
- The refined structure provides detailed insights into Beta-U4O9.
- This work clarifies the crystallographic arrangement of oxygen in this superlattice structure.
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