Lu Shi, Li Fan, Huaya Sun, Daichuan Ma
The effects of an external electric field (EEF) on the crystal structure, nonbonded interaction, sensitivity, and mechanical properties of CL-20/H2O2 and CL-20/H2O energetic solvates have been investigated by classical molecular dynamics simulations. Compared with CL-20/H2O solvate, CL-20/H2O2 solvate possesses stronger O-H···O and C-H···O hydrogen-bond networks, which are more sensitive to the variation of electric field intensity. Such hydrogen-bond frameworks buffer the fluctuation of cell parameters and restrain molecular diffusion under an EEF. Increasing the electric field shortens the N-NO2 trigger bond and reduces its interaction energy, strengthening the intrinsic sensitivity of CL-20 solvates. The conformers of CL-20 molecules transform from the α-phase to the stable ε phase after 0.4 V·Å-1. When an external electric field acts on the CL-20/H2O2 and CL-20/H2O energetic solvates, conformational changes in CL-20 molecules and solvation interactions can effectively reduce stiffness and enhance lattice ductility, reducing hotspot formation and thereby improving thermal safety.