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Updated: Jun 23, 2026
09:05
Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
High-pressure phases of nitrogen
1University of St. Andrews, St. Andrews, KY16 9SS, UK.
Physical Review Letters
|April 28, 2009
Summary
Researchers discovered new high-pressure nitrogen phases using computational methods. These findings reveal efficient molecular packings and predict novel nonmolecular structures at extreme pressures.
Area of Science:
- Materials Science
- Computational Chemistry
- Condensed Matter Physics
Background:
- Nitrogen, a simple diatomic molecule, exhibits complex structural behavior under high pressure.
- Understanding nitrogen's high-pressure phases is crucial for various scientific and technological applications.
Purpose of the Study:
- To identify novel, stable high-pressure phases of nitrogen.
- To investigate the packing arrangements of nitrogen molecules at elevated pressures.
- To predict the existence of nonmolecular nitrogen structures under extreme conditions.
Main Methods:
- Utilized density-functional-theory (DFT) calculations.
- Employed a systematic structure-searching algorithm.
- Calculated the relative stability of candidate nitrogen phases.
Main Results:
- Identified six candidate structures predicted to be more stable than previously known phases.
- Discovered four new molecular structures, offering insights into efficient packing.
- Predicted two new nonmolecular structures stable at very high pressures.
Conclusions:
- The study expands the known phase diagram of high-pressure nitrogen.
- Novel molecular and nonmolecular structures challenge existing models.
- Computational approaches are effective for discovering new materials under extreme conditions.
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