Ab initio thermal rate coefficients for H + NH 3 ⇌ H 2 + NH 2
Ab initio thermal rate coefficients for H + NH 3 ⇌ H 2 + NH 2
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H NH 3 → H 2 NH 2 的从头算热速率系数
DOI：
10.1002/kin.21255
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发表时间：
2019
影响因子：
1.5
通讯作者：
Stanton, John F.
中科院分区：
文献类型：
--
作者：
Nguyen, Thanh Lam;Stanton, John F.
采用高精度外推从头算热理论和半经典过渡态理论相结合的方法，对NH3燃料燃烧中起重要作用的可逆反应NH3+H⇌H2+NH2进行了理论研究。计算的正向反应吸热系数为11.8±0.1kJ/mol，与活化热化学表(ATCT)的值11.5±0.2kJ/mol几乎完全一致。使用这种改进的热化学可以产生更好的速率常数，特别是在低温下。由第一性原理计算得到的正反向反应通道的实验速率常数可在400~2000℃范围内重现(20%以内)。
The reversible reaction NH3+ H ⇌ H2+ NH2, which plays an important role in NH3fuel combustion, is studied with a theoretical approach that combines the high‐accuracy extrapolated ab initio thermochemistry (HEAT) protocol with semiclassical transition state theory (SCTST). The calculated forward reaction is endothermic by 11.8 ± 1 kJ/mol, in nearly perfect agreement with the active thermochemical tables (ATcT) value of 11.5 ± 0.2 kJ/mol. Using this improved thermochemistry yields better rate constants, especially at low temperatures. Experimental rate constants available from 400 to 2000 K for the forward and reverse reaction pathways can be reproduced (within 20%) by the calculations from first principles.