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Updated: Jun 24, 2026
05:50
Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
Orthorhombic aluminium oxyfluoride, AlOF
Alexander D Vasiliev1, Svetlana V Melnikova, Lyudmila I Isaenko
1Institute of Physics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036, Russian Federation. adva@iph.krasn.ru
Summary
Unexpected aluminium oxyfluoride (AlOF) inclusions were discovered within SrAlF(5) crystals. The novel AlOF structure features linked tetrahedral and octahedral polyhedra, differing significantly from previously known phases.
Area of Science:
- Inorganic Chemistry
- Crystallography
- Materials Science
Background:
- Aluminium oxyfluoride (AlOF) is a material of significant interest.
- Previous studies have reported a tetragonal phase of AlOF with a different structure.
Purpose of the Study:
- To identify and characterize unexpected inclusions found in SrAlF(5) crystals.
- To determine the crystal structure of the newly identified aluminium oxyfluoride phase.
Main Methods:
- Single-crystal X-ray diffraction was used to analyze the inclusions.
- Crystal structure refinement was performed to determine atomic positions and bonding.
Main Results:
- The inclusions were identified as aluminium oxyfluoride (AlOF).
- The AlOF structure is composed of linked tetrahedral and octahedral polyhedra.
- The structure exhibits infinite zigzag chains of octahedra along the b axis.
- Al-F(O) bond distances were determined, falling into three distinct groups.
Conclusions:
- A new structural phase of aluminium oxyfluoride (AlOF) has been discovered.
- This AlOF structure is distinct from the previously reported tetragonal phase.
- The findings contribute to the understanding of aluminium oxyfluoride crystallography and phase diversity.
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