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New form of polymeric nitrogen from dynamic shock simulation.

Todd D Beaudet¹, William D Mattson, Betsy M Rice

¹U.S. Army Research Laboratory, RDRL-WMM-E (Bldg. 4600), Aberdeen Proving Ground, Maryland 21005-5069, USA.

The Journal of Chemical Physics

|February 15, 2013

Summary

Researchers discovered a new, stable, porous polymeric nitrogen phase at low pressure. This finding opens new avenues for energetic material applications and understanding amorphous nitrogen structures.

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Area of Science:

Materials Science
Computational Chemistry
Condensed Matter Physics

Background:

Polymeric nitrogen at low pressure is of significant interest for energetic material applications.
Theoretical work suggests meta-stable polymeric nitrogen, supported by experimental evidence of amorphous and cubic-gauche phases.
Limited theoretical work exists on simulating amorphous polymeric nitrogen.

Purpose of the Study:

To simulate amorphous polymeric nitrogen at low pressure.
To investigate novel low-pressure polymeric nitrogen phases.
To explore composite structures involving the new nitrogen form.

Main Methods:

First-principles dynamic shock simulations were initiated from the cubic-gauche nitrogen structure.
Simulations were performed to identify stable low-pressure phases.
Physical characteristics of the new phase were analyzed.

Main Results:

A new, low-pressure, porous form of polymeric nitrogen was unexpectedly discovered.
This new phase exhibits stability at low temperatures.
Composite structures of the new phase and their relation to amorphous nitrogen were explored.

Conclusions:

The discovery of a new stable, porous polymeric nitrogen phase at low pressure is significant.
This finding has implications for the development of novel energetic materials.
Further research into composite structures may elucidate the nature of amorphous polymeric nitrogen.