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Published on: January 15, 2018
A DFT study of the unimolecular decomposition of 1,2,4-butanetriol trinitrate
Weihua Zhu1, Qingli Yan, Aimin Pang
1Institute for Computation in Molecular and Materials Science and Department of Chemistry, Nanjing University of Science and Technology, Nanjing, 210094, China, zhuwh@mail.njust.edu.cn.
Abstract:
To improve understanding of the unimolecular decomposition mechanism of 1,2,4-butanetriol trinitrate (BTTN) in the gas phase, density functional theory calculations were performed to determine various decomposition pathways at the B3LYP/6-311G** level. Two main mechanisms for the unimolecular decomposition of BTTN were found. In the first, homolysis of one of the O-NO2 bonds occurs to form •NO2 and CH2ONO2CHONO2CH2CH2O•, which subsequently decomposes to form CH3CHO + •CHO + 3NO2 + HCHO. In the second, successive HONO elimination reactions yield three HONO and OHCCH2CHONO2CH2ONO2 fragments, which subsequently decompose to form CH3CHO + 2CO + 3HONO. We also found that the first pathway has a slightly lower activation energy than the second. The results show that the pathway involving O-NO2 cleavage is slightly more energetically favorable than that involving HONO elimination.
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