Details

Autor(en) / Beteiligte

• Zeng, Tao
• Li, Hui
• Le Roy, Robert J.
• Roy, Pierre-Nicholas

Titel

"Adiabatic-hindered-rotor" treatment of the parahydrogen-water complex

Ist Teil von

• The Journal of chemical physics, 2011-09, Vol.135 (9), p.094304-094304-15

Ort / Verlag

United States: American Institute of Physics

Erscheinungsjahr

2011

Quelle

American Institute of Physics

Beschreibungen/Notizen

• Inspired by a recent successful adiabatic-hindered-rotor treatment for parahydrogen p H 2 in CO 2 -H 2 complexes [ H. Li , P.-N. Roy , and R. J. Le Roy , J. Chem. Phys. 133 , 104305 ( 2010 ); H. Li , R. J. Le Roy , P.-N. Roy , and A. R. W. McKellar , Phys. Rev. Lett. 105 , 133401 ( 2010 ) ], we apply the same approximation to the more challenging H 2 O-H 2 system. This approximation reduces the dimension of the H 2 O-H 2 potential from 5D to 3D and greatly enhances the computational efficiency. The global minimum of the original 5D potential is missing from the adiabatic 3D potential for reasons based on solution of the hindered-rotor Schrödinger equation of the p H 2 . Energies and wave functions of the discrete rovibrational levels of H 2 O- p H 2 complexes obtained from the adiabatic 3D potential are in good agreement with the results from calculations with the full 5D potential. This comparison validates our approximation, although it is a relatively cruder treatment for p H 2 -H 2 O than it is for p H 2 -CO 2 . This adiabatic approximation makes large-scale simulations of H 2 O- p H 2 systems possible via a pairwise additive interaction model in which p H 2 is treated as a point-like particle. The poor performance of the diabatically spherical treatment of p H 2 rotation excludes the possibility of approximating p H 2 as a simple sphere in its interaction with H 2 O.