The strategy for improving the stability of nitroform derivatives-high-energetic oxidant based on hexanitroethane

To develop high-energetic stability nitroform compounds, three types of nitroform derivatives based on hexanitroethane structure are designed. The guidelines for selecting these compounds are based on (1) constructing a flexible molecule and weakening the external force by elastic deformation and (2) forming negative ion or introducing electron-rich group to eliminate the electron-deficient situation. The conformations and some important properties of them are calculated at B3LYP/6-311 + G(d) level. Based on the bond order and bond dissociation enthalpy analysis, C-NO₂ bond is considered to be the most unstable position, and both of the methods can improve the stability of designed compounds. Based on molecular energy gap (HOMO-LUMO) and density of state (DOS) analysis, it is found that introducing of bridge atoms is helpful to lower the sensitivity, while the construction of anions changes both HOMO-LUMO and DOS which shows obvious ionic properties. A further study on the electrical potential surface shows that the probability for extreme values of designed compounds decreases which is beneficial for high stability. Finally, the explosive properties and impact sensitivity of them are calculated. Results show that their explosive performances are obviously better than current energetic oxidants and some of them maintain low sensitivity.