Effect of Dynamics in the van der Waals Region on the Chemical Kinetics of Nitrogen Containing Molecules
Abstract
We explored the role of the roaming radical mechanism in the thermal decomposition of three small molecules that contain the nitrite and amine groups which are commonly found in propellants. In particular, we studied CH3NO2, which is the smallest nitrite containing molecule to show the effects of roaming, (CH3)2NNH2 (UDMH, for unsymmetrical dimethyl hydrazine), which is used as a bipropellant (with N2O4) in hypergolic rocket fuels, and (iii) CH3NHNO2, which is one of the smallest propellants with both amine and nitrite groups. These molecules exhibited a wide variety of roaming mechanisms, with many of these of considerable importance. The most complex of these, the roaming mediated mechanism for conversion of CH3NHNO2 to CH2NH + HONO, exhibited four separate saddle points in the long-range region of the potential energy surface. Generally, the presence of stronger dipoles, nitrogen lone-pairs, and hydrogen bonding in these nitrogen materials leads to more complex roaming dynamics with lower energy roaming saddle points.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 25, 2021
- Source ID
- W911NF1310251
Entities
People
- Stephen Klippenstein
Organizations
- Army Contracting Command
- United States Army
- University of Chicago