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arXiv · 1410.8021

Collisional excitation of water by hydrogen atoms

F. Daniel·A. Faure·P. J. Dagdigian·M. -L. Dubernet·F. lique·G. Pineau des forêts
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Abstract

We present quantum dynamical calculations that describe the rotational excitation of H$_2$O due to collisions with H atoms. We used a recent, high accuracy potential energy surface, and solved the collisional dynamics with the close-coupling formalism, for total energies up to 12 000 cm$^{-1}$. From these calculations, we obtained collisional rate coefficients for the first 45 energy levels of both ortho- and para-H$_2$O and for temperatures in the range T = 5-1500 K. These rate coefficients are subsequently compared to the values previously published for the H$_2$O / He and H$_2$O / H$_2$ collisional systems. It is shown that no simple relation exists between the three systems and that specific calculations are thus mandatory.

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F. Daniel, A. Faure, P. J. Dagdigian, M. -L. Dubernet, F. lique, G. Pineau des forêts. 2014-10-29. Collisional excitation of water by hydrogen atoms. https://doi.org/10.1093/mnras%2Fstu2287

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