  Regions of energy localization referred to as hotspots are known to govern
shock initiation and the run-to-detonation in energetic materials. Mounting
computational evidence points to accelerated chemistry in hotspots from large
intramolecular strains induced via the interactions between the shockwave and
microstructure. However, definite evidence mapping intramolecular strain to
accelerated or altered chemical reactions has so far been elusive. From a
large-scale reactive molecular dynamics simulation of the energetic material
TATB, we map molecular temperature and intramolecular strain energy prior to
reaction to decomposition kinetics. Both temperature and intramolecular strain
are shown to accelerate chemical kinetics. A detailed analysis of the atomistic
trajectory shows that intramolecular strain can induce a mechanochemical
alteration of decomposition mechanisms. The results in this paper can inform
continuum-level chemistry models to account for a wide range of mechanochemical
effects.
