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Updated: Oct 17, 2025
14:44
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
9.8K
Predicted stable high-pressure phases of copper-nitrogen compounds
Yuting Zhou1, Xingxing Jiang1, Yueshao Zheng1
1Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics & Devices, School of Physics and Electronics, Hunan University, Changsha 410082, People's Republic of China.
Summary
New high-pressure copper-nitrogen compounds were discovered using computational methods. These novel materials exhibit high energy densities, showing promise for advanced energetic applications.
Area of Science:
- Materials Science
- Computational Chemistry
- High-Energy-Density Materials
Background:
- Nitrogen-rich compounds are attractive for high-energy-density applications due to significant differences in nitrogen-nitrogen bond energies.
- Synthesizing stable, high-energy-density copper-nitrogen (Cu-N) compounds remains a significant challenge.
- Previous research synthesized a copper diazenide (P63/mmc-CuN2) under high temperature and pressure, but the full phase diagram is unknown.
Purpose of the Study:
- To computationally explore the pressure-composition phase diagram of copper-nitrogen compounds.
- To identify novel, thermodynamically stable Cu-N compounds at high pressures.
- To assess the potential of these compounds as high-energy-density materials.
Main Methods:
- Utilized first-principles calculations combined with crystal structure prediction.
- Investigated Cu-N compounds across a pressure range of 0-150 GPa.
- Analyzed finite temperature effects, including vibrational energies, on compound stability.
Main Results:
- Predicted four thermodynamically stable Cu-N compounds at high pressures: Pnnm-CuN2, two P-1 space group CuN3 phases (I-CuN3 and II-CuN3), and P21/m-CuN5.
- Identified that vibrational energies are crucial for the stability of the experimentally synthesized P63/mmc-CuN2 at ~55 GPa, contrasting with the predicted Pnnm-CuN2.
- Calculated potential energy densities for the new compounds ranging from 1.57 to 2.74 kJ/g.
Conclusions:
- The study expands the known phase space of copper-nitrogen compounds under high pressure.
- Finite temperature effects significantly influence the stability of specific Cu-N phases.
- The newly predicted compounds represent promising candidates for future high-energy-density material development.
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