Open AccessRotational excitation of mono‐ and doubly‐deuterated water by hydrogen molecules
Author(s) -
Faure A.,
Wiesenfeld L.,
Scribano Y.,
Ceccarelli C.
Publication year - 2012
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2011.20081.x
Subject(s) - deuterium , chemistry , atomic physics , radiative transfer , kinetic isotope effect , excitation , maser , hydrogen , heavy water , coupling (piping) , molecule , physics , materials science , quantum mechanics , metallurgy , organic chemistry , astronomy
Rate coefficients for rotational transitions in HDO and D 2 O induced by H 2 collisions below 300 K are presented. Calculations have been performed at the close‐coupling and coupled‐states levels with the deuterated variants of the H 2 O–H 2 interaction potential of Valiron et al. The HDO–H 2 and D 2 O–H 2 rate coefficients are compared to the corresponding rate coefficients for HDO–He and H 2 O–H 2 , respectively. Significant differences are observed. In particular the new HDO rate coefficients are found to be significantly larger (by up to three orders of magnitude) than the corresponding HDO–He rate coefficients. The impact of the new HDO rate coefficients is examined with the help of non‐LTE radiative transfer calculations. A number of potential HDO maser lines are finally identified, in particular the 80.6 GHz () transition.