Thermal decomposition of a famous high oxidizer arnrnoniurn dinitrarnide （ADN） under high temperatures （2000 and 3000 K） was studied by using the ab initio molecular dynamics method. Two different ternperature-dep...Thermal decomposition of a famous high oxidizer arnrnoniurn dinitrarnide （ADN） under high temperatures （2000 and 3000 K） was studied by using the ab initio molecular dynamics method. Two different ternperature-dependent initial decomposition mechanisms were observed in the unirnolecular decomposition of ADN, which were the intrarnolecular hydrogen transfer and N-NO2 cleavage in N（NO2） . They were competitive at 2000 K, whereas the forrner one was predominant at 3000 K. As for the rnultimolecular decomposition of ADN, four different initial decomposition reactions that were also ternperature-dependent were observed. Apart from the aforernentioned rnechanisrns, another two new reactions were the interrnolecular hydrogen transfer and direct N-H cleavage in NH4＋. At the temperature of 2000 K, the N-NO2 cleavage competed with the rest three hydrogen-related decomposition reactions, while the direct N-H cleavage in NH4＋ was predominant at 3000 K. After the initial decomposition, it was found that the temperature increase could facilitate the decomposition of ADN, and would not change the key decomposition events. ADN decomposed into small molecules by hydrogen-prornoted simple, fast and direct chemical bonds cleavage without forrning any large intermediates that rnay impede the decomposition. The main decomposition products at 2000 and 3000 K were the same, which were NH3, NO2, NO, N2O, N2, H2O, and HNO2.展开更多
基金supported by the Fundamental Research Funds for the Central Universities (No.30916011315)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe Fundamental Research Funds for the Central Universities (No.30916011317)
文摘Thermal decomposition of a famous high oxidizer arnrnoniurn dinitrarnide （ADN） under high temperatures （2000 and 3000 K） was studied by using the ab initio molecular dynamics method. Two different ternperature-dependent initial decomposition mechanisms were observed in the unirnolecular decomposition of ADN, which were the intrarnolecular hydrogen transfer and N-NO2 cleavage in N（NO2） . They were competitive at 2000 K, whereas the forrner one was predominant at 3000 K. As for the rnultimolecular decomposition of ADN, four different initial decomposition reactions that were also ternperature-dependent were observed. Apart from the aforernentioned rnechanisrns, another two new reactions were the interrnolecular hydrogen transfer and direct N-H cleavage in NH4＋. At the temperature of 2000 K, the N-NO2 cleavage competed with the rest three hydrogen-related decomposition reactions, while the direct N-H cleavage in NH4＋ was predominant at 3000 K. After the initial decomposition, it was found that the temperature increase could facilitate the decomposition of ADN, and would not change the key decomposition events. ADN decomposed into small molecules by hydrogen-prornoted simple, fast and direct chemical bonds cleavage without forrning any large intermediates that rnay impede the decomposition. The main decomposition products at 2000 and 3000 K were the same, which were NH3, NO2, NO, N2O, N2, H2O, and HNO2.
