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Updated: Jul 9, 2026

Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
Adiabatic capture theory applied to N+NH-->N2+H at low temperature
Terry J Frankcombe1, Gunnar Nyman
1Physical Chemistry, Department of Chemistry, Göteborg University, SE-412 96 Göteborg, Sweden. terry@chem.gu.se
Abstract:
The adiabatic capture centrifugal sudden approximation (ACCSA) has been applied to the ground state reaction N+NH-->N2+H over the temperature range 2-300 K using an existent potential energy surface. The resultant thermal rate constants are in agreement with available rate constants from quasi-classical trajectory calculations but are significantly larger than the available experimentally derived rate. The calculated rate constants monotonically increase with increasing temperature but could only be approximately described with a simple Arrhenius-like form. Subtle quantum effects are evident in the initial rotational state resolved cross sections and rate constants.
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