Crystal Morphology Analysis And Comparison Of Prediction Method Of HMX

1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)is the most common explosive and best explosive used in the military,it has higher mechanical sensitivity and better detonation performance.Mechanical sensitivity was affected by crystal morphology,in order to study the influence of solvent on the crystal growth morphology of HMX,the crystal morphology of HMX crystals in different solvents was predicted by three theoretical models.It provided theoretical basis for the development of low-sensitivity HMX crystals.The vacuum morphology of HMX was predicted by adhesion energy model.The results showed that the COMPASS force field is suitable for the study of HMX.The important growth faces of HMX in vacuum were(0 1 1),(1 1 0),(1 0–1),(0 2 0)and(1 0 1),the aspect ratio was 1.96.The analysis of different crystal plane structures in HMX showed that the(1 0–1)crystal plane is the roughest and the(1 0 1)crystal plane is the smoothest.The intramolecular and intermolecular interactions in HMX crystals were dominated by O···H/H···O contacts.The relative growth rates of HMX crystals in eight solvents were simulated and calculated by the modified adhesion energy model 1(defined as MAE₁),then the morphology of HMX crystals in eight solvents was predicted.According to the radial distribution function,there were hydrogen bonding,van der Waals interaction and electrostatic interaction between solvent molecules and crystal planes.According to the solvent diffusion properties,the diffusion of DMSO and AC were the most obvious.The solvent density analysis showed that(0 1 1)surface has the maximum density peak and(0 2 0)surface has the minimum density peak.The results of morphology prediction and aspect ratio calculation showed that DMSO and AC solvents are more favorable for the morphology of HMX crystals to be spherical.The morphology of HMX crystals in DMSO was predicted using the modified adhesion energy model 2(defined as MAE₂)and the occupancy model,and then compared with the experimental results.The results showed that in DMSO solvent,the crystal morphology predicted by the occupancy model is closer to the experimental value.The effect of crystal morphology at different temperatures was studied,and the solvent density distribution and diffusivity of DMSO at different temperatures were analyzed.The results showed that DMSO molecules diffused more easily and the solvent density peak increased with the increase of temperature.Temperature had little effect on HMX crystal morphology.