On the burning of air

Air is shown to burn (in theory, using two complementary procedures) under the unusual combination of conditions made possible within a cluster heated by a supersonic impact at an inert surface. Both clusters of neat N2/O2 and clusters containing several N2 and O2 molecules within a rare gas envelope have been studied. The principal reaction is N2 + O2 → 2NO which proceeds via a four-center mechanisms. The four-center reaction N2 + O2 → N2O + O leads to N2O which is quite hot, as is to be expected on the basis of kinematic considerations, and is efficiently destroyed as the cluster expands. During the early, compression, stage multi- (>4) center reactions readily occur. The results of molecular dynamics simulations using a many-body potential are well accounted for by a distribution of products of maximum entropy subject to conservation of energy, matter and charge.