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The application of high energy density explosive CL-20 is limited due to its high sensitivity and low safety. In order to reduce the sensitivity of CL-20, CL-20 and low-sensitivity RDX were combined at the molecular level to form cocrystals, so as to improve the performance of explosives. At present, CL-20/RDX cocrystal theory is not mature enough, for Studying the mechanism of CL-20/RDX cocrystal formation and its effect on CL-20 and to provide some theoretical support for the preparation of CL-20 cocrystal. Molecular dynamics simulations of CL-20/RDX cocrystal at different temperatures (200K,298K,400K) are performed. The simulation results were analyzed by radial distribution function (RDF), Hirshfeld surface analysis, and growth simulation. The results show that the CL-20/RDX cocrystal g(r) peak values of O…H at 200K, 298K, and 400K were 1.55, 1.76, and 2.00, respectively; as the temperature of the cocrystal decreases, the hydrogen bonding interaction strengthens. The g(r) peak value of the N-N bond was higher than that of the pure component CL-20, indicating that the cocrystal enhanced the strength of the N-N bond and reduced the sensitivity of CL-20. At the same temperature, the g(r) value of the N...N bond is lower than N...O, and CL-20 decomposition starts from the N-N bond. Hirshfeld surface analysis showed that the O...H contact contribution to the Hirshfeld surface area was 38.2%, which accounted for the largest proportion of interactions, and the de+di value was the smallest, that is, the interaction distance was the shortest, indicating that the driving force of CL-20/RDX cocrystal formation was derived from hydrogen bonding. The strong interaction of the cocrystal is mainly generated at the nitro group, and the hydrogen bond force of the central molecule CL-20 as a hydrogen bond donor is greater than that of a hydrogen bond acceptor. The simulated morphology is long columnar, which is similar to the experimentally prepared morphology, and its rounded shape has certain advantages in terms of sensitivity.
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