title: Formation and decay of tetrazane derivatives--a Car-Parrinello molecular dynamics study.
abstract: The complications during flight 510 of the Ariane Project were ascribed to problems in the upper stage engine that employs the bipropellant monomethylhydrazine (MMH) and nitrogen tetroxide (NTO). This has led to the question what conditions or reactions possibly cause an uncontrolled behaviour in the combustion process of MMH/NTO. We use first-principles molecular dynamics to investigate the reactions of the hypergolic mixture in different chemical situations. It was possible to observe the ultrafast redox reaction between the reactants on the timescale of an unconstrained simulation. We show that electrostatic attraction is crucial for the understanding of this reaction. Besides a cold reaction preceding the ignition, a reaction path leading to the highly reactive compound dimethyltetrazane could be identified.
authors.affiliation: Department of Chemistry and Biochemistry, Center for Nanoscience, and Nanosystems Initiative Munich, Ludwig-Maximilians-Universität München, Butenandtstr. 11, D-81377 München.
authors.forename: Christel
authors.initials: C
authors.lastname: Nonnenberg
authors.forename: Irmgard
authors.initials: I
authors.lastname: Frank
mesh_terms: D003198:Computer Simulation; D008958:Models, Molecular; D015394:Molecular Structure; D009002:Monomethylhydrazine / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D010084:Oxidation-Reduction; D011789:Quantum Theory; D055672:Static Electricity
chemical_list: D009589:Nitrogen Oxides; C015167:nitrogen tetroxide; D009002:Monomethylhydrazine