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Updated: Sep 27, 2025
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
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A four-dimensional model for the Ba-Ti-O dodecagonal quasicrystal
1Faculty of Science, Department of Applied Physics, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.
Summary
Researchers developed a four-dimensional (4D) model for the first oxide dodecagonal quasicrystal, observed in a Ba-Ti-O thin film. This model aids in understanding quasicrystal structures and their atomic arrangements.
Area of Science:
- Materials Science
- Crystallography
- Thin Film Physics
Background:
- Quasicrystals exhibit unique atomic arrangements with long-range order but no translational symmetry.
- Dodecagonal quasicrystals are characterized by 12-fold rotational symmetry.
- Oxide-based quasicrystals are less explored compared to metallic counterparts.
Purpose of the Study:
- To present a four-dimensional (4D) model of the first discovered oxide dodecagonal quasicrystal.
- To describe the atomic structure and lattice parameters of this novel quasicrystal.
- To derive periodic approximants from the 4D model.
Main Methods:
- Utilizing a tile decoration model based on dodecagonal Niizeki-Gähler tiling.
- Defining occupation domains and 4D positional vectors within the model.
- Introducing linear phason strains to derive periodic approximants.
Main Results:
- A 4D model with a dodecagonal lattice constant (ad) of 8.39 Å was established.
- The model incorporates four distinct occupation domains.
- Two periodic approximants (sigma-phase and a 25.6 Å approximant) of the Ba-Ti-O quasicrystal were successfully derived.
Conclusions:
- The presented 4D model provides a framework for understanding the structure of oxide dodecagonal quasicrystals.
- The methodology allows for the derivation of periodic approximants, facilitating experimental validation.
- This work opens avenues for exploring other oxide-based quasicrystalline materials.
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