Density functional theory was employed to investigate the four structures (a, b, c, d) of CL-20/NQ cocrystal. The intermolecular interaction, explosive property, and crystal structure were analyzed and predicted in this paper. The results showed that CL-20/NQ cocrystal is formed by a series of the week hydrogen bonding interactions and van der Waals forces. And the interaction energies of four structures are in the order of c > b > d > a. Moreover, the sensitivity and detonation velocity of CL-20/NQ cocrystal have a little decrease compared with those of the isolated CL-20, and it is obvious expression in structures b and c. Finally, the CL-20/NQ cocrystal is most likely to crystallize in monoclinic system and P21/c space group, its corresponding cell parameters are a = 13.9820?, b = 14.0933?, c = 9.5160?, α = γ = 90.000°, β = 93.853°, V = 1870.910?3, Z = 4. These results will provide a theoretical direction for further research of CL-20/NQ cocrystal.
