Time-resolved molecular changes in a chemically reacting shocked energetic liquid

Experimental measurements, using Raman spectroscopy, are presented that demonstrate the ability to continuously monitor molecular changes associated with the onset of a chemical reaction in a shocked condensed explosive. In shock reverberation experiments to a peak pressure of 14 GPa, liquid nitromethane with ethylenediamine additive (0.1 wt%) undergoes an irreversible chemical change; direct evidence for CN bond scission is presented. In contrast, pure nitromethane shows completely reversible behavior at comparable shock pressures. The present data support the hypothesis that the addition of an amine lowers the activation energy for CN bond scission.