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Updated: May 17, 2026

Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
Ortho-para-H2 conversion by hydrogen exchange: comparison of theory and experiment
François Lique1, Pascal Honvault, Alexandre Faure
1LOMC - UMR 6294, CNRS-Université du Havre, 25 rue Philippe Lebon, BP 540, 76058, Le Havre, France. francois.lique@univ-lehavre.fr
Abstract:
We report fully-quantum time-independent calculations of cross sections and rate coefficients for the collisional (de)excitation of H(2) by H. Our calculations are based on the H(3) global potential energy surface of Mielke et al. [J. Chem. Phys. 116, 4142 (2002)]. The reactive hydrogen exchange channels are taken into account. We show that the ortho-para and para-ortho conversion of H(2) are significant processes at temperatures above ~300 K and for the last process we provide the first comparison with available experimental rate coefficients between 300 and 444 K. The good agreement between theory and experiment is a new illustration of our detailed understanding of the simplest chemical reaction. The importance of the ortho-para-H(2) conversion by hydrogen exchange in astrophysics is discussed.
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