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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
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Pressure-induced planar N6 rings in potassium azide
Jie Zhang1, Zhi Zeng2, Hai-Qing Lin3
1Key Laboratory of Materials Physics, Institute of Solid State Physics, CAS, and Department of Physics, University of Science and Technology of China, Hefei 230031, China.
Scientific Reports
|March 13, 2014
Summary
High pressure studies reveal potassium azide (KN3) transitions from an insulator to a metallic phase. At extreme pressures, N6 rings polymerize, offering insights into azide anion behavior under compression.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Computational Chemistry
Background:
- Potassium azide (KN3) is a compound with potential applications.
- Understanding its high-pressure behavior is crucial for materials science.
- Azide anions (N3-) exhibit complex structural transformations under pressure.
Purpose of the Study:
- To identify stable high-pressure phases of potassium azide (KN3).
- To investigate the pressure-induced phase transitions in KN3.
- To elucidate the structural evolution of N3- anions under extreme compression.
Main Methods:
- Utilized first-principles calculations.
- Employed evolutionary algorithms for phase prediction.
- Analyzed structural stability and electronic properties at varying pressures.
Main Results:
- Identified a stable I4/mcm insulating phase below 22 GPa, consistent with experimental data.
- Observed a transition to a C2/m insulating phase with increasing pressure.
- Predicted a metallic P6/mmm phase above 40 GPa featuring six-membered nitrogen rings.
- Suggested potential polymerization of N6 rings above 100 GPa due to increased compactness.
Conclusions:
- KN3 undergoes significant structural phase transitions under high pressure.
- The formation of N6 rings and their polymerization are key to understanding pressure effects on KN3.
- Computational methods accurately predict high-pressure behavior and phase transformations in KN3.
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