Han, Si-Ping and van Duin, Adri C. T. and Goddard, William A., III and Strachan, Alejandro (2011) Thermal Decomposition of Condensed-Phase Nitromethane from Molecular Dynamics from ReaxFF Reactive Dynamics. Journal of Physical Chemistry B, 115 (20). pp. 6534-6540. ISSN 1520-6106 http://resolver.caltech.edu/CaltechAUTHORS:20110607-105428231
- Published Version
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20110607-105428231
We studied the thermal decomposition and subsequent reaction of the energetic material nitromethane (CH_3NO_2) using molecular dynamics with ReaxFF, a first principles-based reactive force field. We characterize the chemistry of liquid and solid nitromethane at high temperatures (2000−3000 K) and density 1.97 g/cm^3 for times up to 200 ps. At T = 3000 K the first reaction in the decomposition of nitromethane is an intermolecular proton transfer leading to CH_3NOOH and CH_2NO_2. For lower temperatures (T = 2500 and 2000 K) the first reaction during decomposition is often an isomerization reaction involving the scission of the C−N bond the formation of a C−O bond to form methyl nitrate (CH_3ONO). Also at very early times we observe intramolecular proton transfer events. The main product of these reactions is H_2O which starts forming following those initiation steps. The appearance of H_2O marks the beginning of the exothermic chemistry. Recent quantum-mechanics-based molecular dynamics simulations on the chemical reactions and time scales for decomposition of a crystalline sample heated to T = 3000 K for a few picoseconds are in excellent agreement with our results, providing an important, direct validation of ReaxFF.
|Additional Information:||© 2011 American Chemical Society. Received: October 31, 2010 Revised: March 28, 2011. Publication Date (Web): May 4, 2011. S.H. would like to thank the Seaborg Institute for a summer fellowship, Jason Keith for preparation of the ReaxFF training set, and P.W.K. Rothemund for help in formatting the manuscript. Work at Los Alamos was supported by the ASC Materials and Physics modeling project and DARPA (program manager Carey Schwatz). Work at Caltech is supported by ONR (N00014-09-1-0634, program manager Cliff Bedford), LANL (65287-001-08, program manager Ed Kober), and DARPA (program manager Carey Schwatz).|
|Official Citation:||Thermal Decomposition of Condensed-Phase Nitromethane from Molecular Dynamics from ReaxFF Reactive Dynamics Si-ping Han, Adri C. T. van Duin, William A. Goddard III, Alejandro Strachan The Journal of Physical Chemistry B 2011 115 (20), 6534-6540|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Ruth Sustaita|
|Deposited On:||07 Jun 2011 18:34|
|Last Modified:||26 Dec 2012 13:17|
Repository Staff Only: item control page