Thermal decomposition of RDX from reactive molecular dynamics

Alejandro Strachan, Edward M. Kober, Adri C.T. Van Duin, Jonas Oxgaard, William A. Goddard

Research output: Contribution to journalArticle

291 Citations (Scopus)

Abstract

We use the recently developed reactive force field ReaxFF with molecular dynamics to study thermal induced chemistry in RDX [cyclic-[CH 2N(NO 2)] 3] at various temperatures and densities. We find that the time evolution of the potential energy can be described reasonably well with a single exponential function from which we obtain an overall characteristic time of decomposition that increases with decreasing density and shows an Arrhenius temperature dependence. These characteristic timescales are in reasonable quantitative agreement with experimental measurements in a similar energetic material, HMX [cyclic-[CH 2N(NO 2)] 4]. Our simulations show that the equilibrium population of CO and CO 2 (as well as their time evolution) depend strongly of density: at low density almost all carbon atoms form CO molecules; as the density increases larger aggregates of carbon appear leading to a C deficient gas phase and the appearance of CO 2 molecules. The equilibrium populations of N 2 and H 2O are more insensitive with respect to density and form in the early stages of the decomposition process with similar timescales.

Original languageEnglish (US)
Article number054502
JournalJournal of Chemical Physics
Volume122
Issue number5
DOIs
StatePublished - Aug 8 2005

Fingerprint

RDX
Carbon Monoxide
thermal decomposition
Molecular dynamics
Pyrolysis
molecular dynamics
Carbon
Decomposition
Molecules
Exponential functions
Potential energy
methylidyne
HMX
decomposition
Gases
carbon
exponential functions
Atoms
Temperature
field theory (physics)

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this

Strachan, Alejandro ; Kober, Edward M. ; Van Duin, Adri C.T. ; Oxgaard, Jonas ; Goddard, William A. / Thermal decomposition of RDX from reactive molecular dynamics. In: Journal of Chemical Physics. 2005 ; Vol. 122, No. 5.
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Thermal decomposition of RDX from reactive molecular dynamics. / Strachan, Alejandro; Kober, Edward M.; Van Duin, Adri C.T.; Oxgaard, Jonas; Goddard, William A.

In: Journal of Chemical Physics, Vol. 122, No. 5, 054502, 08.08.2005.

Research output: Contribution to journalArticle

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AU - Strachan, Alejandro

AU - Kober, Edward M.

AU - Van Duin, Adri C.T.

AU - Oxgaard, Jonas

AU - Goddard, William A.

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