Reactive nanojets: Nanostructure-enhanced chemical reactions in a defected energetic crystal

Nanofluidics of chemically reactive species has enormous technological potential and computational challenge arising from coupling quantum-mechanical accuracy with largescale fluid phenomena. Here, we report a million-atom reactive force field molecular dynamics simulation of shock initiation of an energetic crystal with a nanometer-scale void. The simulation reveals the formation of a nanojet which focuses into a narrow beam at the void. This, combined with the excitation of vibrational modes through enhanced intermolecular collisions by the free volume of the void, catalyzes chemical reactions that do not occur otherwise. We also observe a pinning-depinning transition of the shock wave front at the void at increased particle velocity and the resulting localization-delocalization transition of the vibrational energy. (C) 2007 American Institute of Physics.