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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Na3Ca2TaO6, a rock-salt superstructure phase with a fully ordered cation arrangement
1Institute for Advanced Materials Processing, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan. yamane@ibis.iamp.tohoku.ac. jp.
Acta Crystallographica. Section C, Crystal Structure Communications
|October 12, 2000
Summary
Trisodium dicalcium tantalum hexaoxide, a novel quaternary oxide, exhibits an ordered rock-salt crystal structure. This cation-ordered superstructure features sodium, calcium, and tantalum atoms arranged in specific octahedral sites.
Area of Science:
- Solid-state chemistry
- Materials science
- Crystallography
Background:
- Quaternary oxides are complex materials with diverse applications.
- Understanding crystal structures is crucial for predicting material properties.
- Rock-salt phases and their ordered variants are of significant interest in materials science.
Purpose of the Study:
- To characterize the crystal structure of trisodium dicalcium tantalum hexaoxide.
- To determine if this compound is isostructural with known ordered rock-salt phases.
- To elucidate the atomic arrangement within the cation-ordered superstructure.
Main Methods:
- Crystallographic analysis
- Powder X-ray diffraction (PXRD)
- Single-crystal X-ray diffraction (SCXRD)
Main Results:
- Trisodium dicalcium tantalum hexaoxide was identified as a quaternary oxide.
- The compound is isostructural with Li(3)Ni(2)TaO(6), a partially ordered rock-salt phase.
- Na, Ca, and Ta atoms occupy specific octahedral sites, forming a cation-ordered superstructure.
Conclusions:
- The crystal structure of trisodium dicalcium tantalum hexaoxide has been determined.
- The compound adopts an ordered arrangement of cations within an octahedral framework.
- This ordered superstructure provides insights into the formation and properties of related complex oxides.
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