Morphology Of CL-20and Molecular Dynamic Simulation On Co-crystal Of CL-20/TATB

anitro-2,4,6,8,10,12-hexaazatetracyclo (CL-20) is a multi nitramines cage compoundappeared in recent years,with the highest energy level and a very broad application prospects.Based on the internal structure of the crystal, the effect of the solvent ethanol and ethyl acetateon CL-20crystal morphology was simulated using molecular dynamics. The adhesion energywas calculated and modified, and CL-20crystal morphology obtained by evaporation of thesolvent and crystallization was compared to the modified dynamics simulation results. Thecrystallization process in solvents was revealed through theoretical data, which would have avery important significance in the control of crystallization process and choice of solvent inexplosives research and development process. Moreover, based on the design principle ofco-crystal and molecular simulation technology,CL-20and the recognized insensitiveexplosive1,3,5-triamino-2,4,6-trinitrobenzene(TATB) was combined at the molecular level,thereby changing the internal configuration of explosives and forming a kind ofmulti-component molecular crystal structure(co-crystal) with specific structure and properties,which was expected to form a high-energy insensitive co-crystal explosive and would providea new solution to the high energy and security of energetic materials and theoretical support inlaboratory co-crystal research. The main contents are as follows:(1) By molecular simulation method starting from the internal crystal structure of CL-20,Possible theories into the crystal morphology under vacuum CL-20was calculated by usingBFDH、AE and Equilibrium Morphology contained in Morphology module of Material studio.The theoretical simulation of the resulting crystal morphology and crystal habit knowncompared to the actual, the results show that the results obtained by BFDH and EquilibriumMorphology are differences with actual results, AE quite coincide with the actual results. Tostudy the morphology and mechanism of CL-20crystal in vacuum, ethanol and ethyl acetate,its crystal model, six kinds of sorption model among ethanol, ethyl acetate, and crystal surfaceare constructed based on CL-20cell parameters and its important crystal surfaces Moleculardynamic simulations are used to calculated the sorption energy between important crystal surfaces (hkl) and solvent, and the attachment energy of hkl are fixed according to it.Attachment energy model is used to predicted the crystal morphology of CL-20in vacuum,ethyl acetate and methanol, The results shows that ethanol have no influence on crystal purity.(2) Six Co-crystal models of CL-20/TATB are constructed based on cell parameters, themain growth surfaces and forming principle of their eutectics. The radial distribution function,X-ray power diffraction and energy calculation of structures are launched after MD process isequilibrium. The results shows that hydrogen bond exists in the six eutectic structures; XRDdiffraction peak in stochastic substituted model are similar with pure CL-20’s, XRDdiffraction peak in main surface differs from CL-20’s and TATB’s and new peaks appear; theenergy of (10-1) crystal surface in eutectic structures is lowest and construction shows moststable. The eutectic model of CL-20substituted by TATB on its (10-1) surface is easier to beformed.