Molecular Modeling on Morphology of 3,4-Bis(3-nitrofurazan-4-yl)furoxan Crystals in Dichloroethane or Benzene Mixture Solvents.

According to the experiments, DNTF crystallizes in benzene/methylbenzene (1:1), benzene/methylbenzene/ethanol (2:3:5), and sym-dichloroethane solvents into two similar crystal shapes, namely strip and tetrahedral. There is a possibility that solvent changes the crystal morphology. In order to explain this phenomenon, the DNTF growth interface model was constructed according to the actual solution environment. The interaction energy between the solvent phase and the DNTF crystal face was studied by means of molecular dynamics simulation. The crystal morphology of DNTF was predicted using the classical modified attachment energy model (MAE) in benzene, methylbenzene, benzene/methylbenzene (1:1), benzene/methylbenzene/ethanol (2:3:5), and sym-dichloroethane. The results show that the DNTF growths are mainly dominated by the (011), (001), (101), (110), (111), and (11[Formula: see text]) faces in vacuum. However, only a few faces will remain in the solvents, of which the (011) and (101) faces are exposed in benzene, methylbenzene, and benzene/methylbenzene (1:1), and only the (111) faces constitute the crystal shape of the DNTF in benzene/methylbenzene/ethanol (2:3:5) and sym-dichloroethane. The predicted results successfully explained the observed phenomena in the experiment. The simulation results can provide some guidance for the crystallization process of DNTF.