Jump to main content
Jump to site search

Issue 33, 2016
Previous Article Next Article

Rovibrational transitions of the methane–water dimer from intermolecular quantum dynamical computations

Author affiliations

Abstract

Rovibrational quantum nuclear motion computations, with J = 0, 1, and 2, are reported for the intermolecular degrees of freedom of the methane–water dimer, where J is the quantum number describing the overall rotation of the complex. The computations provide the first explanation of the far-infrared spectrum of this complex published in J. Chem. Phys., 1994, 100, 863. All experimentally reported rovibrational transitions, up to J = 2, can be assigned to transitions between the theoretically computed levels. The deviation of the experimental and computed rovibrational transitions is 0.5 cm−1 for the ortho and 2 cm−1 for the para species with a variance of 0.005 cm−1. In addition to a lower systematic error, the overall agreement of theory and experiment is also better for the ortho species (involving ortho-H2O). Most importantly, for this species all levels of the 24-fold tunneling splitting manifold corresponding to the zero-point vibration (ZPV) are involved in at least one experimentally reported transition. For the para species there are a few energy levels in the computed ZPV manifold that are not involved in the reported experimental transitions. Furthermore, computed energy levels are identified that correspond to the ZPV tunneling splitting manifold of the secondary minimum structure of the dimer, which presumably appear in rovibrational transitions in the same energy regime as the observed transitions, but have not been experimentally reported.

Graphical abstract: Rovibrational transitions of the methane–water dimer from intermolecular quantum dynamical computations

Back to tab navigation

Supplementary files

Publication details

The article was received on 06 May 2016, accepted on 15 Jun 2016 and first published on 17 Jun 2016


Article type: Paper
DOI: 10.1039/C6CP03062A
Citation: Phys. Chem. Chem. Phys., 2016,18, 22816-22826
  •   Request permissions

    Rovibrational transitions of the methane–water dimer from intermolecular quantum dynamical computations

    J. Sarka, A. G. Császár, S. C. Althorpe, D. J. Wales and E. Mátyus, Phys. Chem. Chem. Phys., 2016, 18, 22816
    DOI: 10.1039/C6CP03062A

Search articles by author

Spotlight

Advertisements