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Title: Ab initio thermal rate coefficients for H + NH3⇌ H2+ NH2

Journal Article · · International Journal of Chemical Kinetics
DOI: https://doi.org/10.1002/kin.21255 · OSTI ID:1609782
ORCiD logo [1];  [2]
  1. Univ. of Florida, Gainesville, FL (United States); DOE/OSTI
  2. Univ. of Florida, Gainesville, FL (United States)
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The reversible reaction NH3 + H ⇌ H2 + NH2, which plays an important role in NH3 fuel 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.

Research Organization:
University of Texas, Austin, TX (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
FG02-07ER15884
OSTI ID:
1609782
Journal Information:
International Journal of Chemical Kinetics, Journal Name: International Journal of Chemical Kinetics Journal Issue: 5 Vol. 51; ISSN 0538-8066
Publisher:
WileyCopyright Statement
Country of Publication:
United States
Language:
English

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Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Chemistry
HEAT
NH3
SCTST
VPT2