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11:32
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
X-ray diffraction study of K3NdSi7O17: a new framework silicate with a linear Si-O-Si bond
1Materials Science, California Institute of Technology, Pasadena, CA 91125, USA. smhaile@caltech.edu
Acta Crystallographica. Section B, Structural Science
|September 28, 2000
Summary
Researchers discovered a new silicate compound, tripotassium neodymium heptasilicate (K(3)NdSi(7)O(17)), during a search for fast-ion conductors. This novel material exhibits a unique crystal structure with a 180-degree Si-O-Si bond angle.
Area of Science:
- Solid State Chemistry
- Crystallography
- Materials Science
Background:
- Exploration of the K(2)O-Nd(2)O(3)-SiO(2) system is crucial for discovering new materials.
- Fast-ion conductors (FICs) are essential for advanced energy storage applications.
Purpose of the Study:
- To synthesize and characterize novel compounds within the high-silica region of the K(2)O-Nd(2)O(3)-SiO(2) system.
- To identify potential new fast-ion conductors (FICs).
Main Methods:
- Hydrothermal synthesis was employed to investigate the K(2)O-Nd(2)O(3)-SiO(2) system.
- Single-crystal X-ray diffraction was used to determine the crystal structure of the new compound.
Main Results:
- A new compound, tripotassium neodymium heptasilicate (K(3)NdSi(7)O(17)), was successfully synthesized.
- The crystal structure was solved using single-crystal X-ray methods, revealing crystallization in space group P3 with specific lattice constants.
- The structure features an interrupted silicate framework with Nd octahedra and K polyhedra, and an unusual 180-degree Si-O-Si bond angle.
Conclusions:
- Tripotassium neodymium heptasilicate (K(3)NdSi(7)O(17)) is a novel compound with a unique structural motif.
- The discovery of K(3)NdSi(7)O(17) expands the known structural diversity of silicates.
- No known isomorphs of K(3)NdSi(7)O(17) exist, highlighting its uniqueness.
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