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Updated: Nov 16, 2025
11:32
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
21.9K
Tungsten Hexanitride with Single-Bonded Armchairlike Hexazine Structure at High Pressure
Nilesh P Salke1, Kang Xia2,3, Suyu Fu4
1Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China.
Physical Review Letters
|February 26, 2021
Summary
A new tungsten nitride (WN6) phase was discovered under high pressure. This ultrastiff and tough material features unique hexazine rings, suggesting potential for novel nitride development.
Area of Science:
- Materials Science
- Solid-State Chemistry
- High-Pressure Physics
Background:
- Tungsten nitrides are known for their diverse structures and potential applications.
- Investigating novel phases under extreme conditions can lead to materials with unique properties.
Purpose of the Study:
- To discover and characterize a new high-pressure phase of tungsten nitride.
- To elucidate the structural, bonding, and mechanical properties of this novel phase.
Main Methods:
- Synthesis of WN6 phase by heating tungsten in nitrogen at 126-165 GPa.
- X-ray diffraction (XRD) for structural refinement.
- Raman spectroscopy to confirm bonding characteristics.
- Density functional theory (DFT) calculations for mechanical and electronic properties.
Main Results:
- Discovery of a WN6 phase with a unit cell in space group R3[over ¯]m.
- Identification of armchair-like hexazine (N6) rings with N-N single bonds, confirmed by Raman spectroscopy.
- DFT calculations indicated balanced W-N and N-N interactions, resulting in ultrastiff and tough material properties.
- Observed long N-N bond lengths and a pressure-enhanced electronic band gap.
Conclusions:
- The newly discovered WN6 phase exhibits exceptional stiffness and toughness due to its unique structure.
- The presence of hexazine rings and tunable electronic properties suggests potential for designing novel nitride materials.
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