中文摘要：

在B3LYP／6-31G（d，P）、MP4（SDTQ）／6-31G（d，P）、G3MP283等多种水平下计算了FOX-7的两种有分歧的起始热分解方式反应物、中间体和过渡态的能量，并以高水平的G3MP283方法得到的能量为准，计算了硝基断裂反应和异构化反应在温度范围250-3300K下的速率常数。结果表明，在高温下FOX-7的主要起始热分解方式是C-NO2键断裂，与从头算分子动力学模拟结果相一致。探讨了FOX-7分解生成的NO2对FOX-7分解的影响，计算结果表明，有NO2存在时，分解能垒会降低，FOX-7的分解会加速。

英文摘要：

B3LYP/6-31G（d, p）, MP4（SDTQ）/6-31G（d, p） and G3MP2B3 methods were used to calculate the energy of the decomposition species of FOX-7. Based on the energy obtained by G3MP2B3 method, the rate constants of C-NO2 cleavage and nitro-to-nitrite rearrangement were calculated in the temperature range of 250 -3300 K. It is found that C-NO2 cleavage is the dominant initial thermal decomposition step at high temperature which is consistent with the conclusion based on ab initio molecular dynamics simulation. The effects of NO2 on the FOX-7 decomposition were investigated. Results show that the decomposition energy barrier becomes lower when NO2 reacts with FOX-7.