Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential

doi:https://doi.org/10.1021/jp991723b

Title: Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential

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Abstract

The authors report variational calculations of vibrational energies of CH{sub 4}, CH{sub 3}D, CH{sub 2}D{sub 2}, CHD{sub 3}, and CD{sub 4} using the code Multimode and the ab initio force field of Lee and co-workers [Lee, T.J.; Martin, J.M.L.; Taylor, P.R.--J.Chem.Phys. 1995, 102, 254], re-expressed using Morse variables in the stretch displacements. Comparisons are made with experimental energies for CH{sub 4} with this potential, and then small adjustments are made to the potential to improve agreement with experiment for CH{sub 4}. Calculations for the isotopomers are done using the adjusted potential and compared with experiment. Additional vibrational energies and assignments not reported experimentally are also given for CH{sub 4} and the isotopomers. Exact rotational-vibrational energies of CH{sub 4} are also reported for J = 1.

Authors:: Carter, S; Bowman, J M

Publication Date:: 2000-03-23

Research Org.:: Emory Univ., Atlanta, GA (US)

OSTI Identifier:: 20026893

Resource Type:: Journal Article

Journal Name:: Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory

Additional Journal Information:: Journal Volume: 104; Journal Issue: 11; Other Information: PBD: 23 Mar 2000; Journal ID: ISSN 1089-5639

Country of Publication:: United States

Language:: English

Subject:: 03 NATURAL GAS; METHANE; DEUTERIUM COMPOUNDS; SPECTROSCOPY; HAMILTONIANS; VIBRATIONAL STATES; ROTATION-VIBRATION MODEL

Citation Formats


                    Carter, S, and Bowman, J M. Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential.  United States: N. p., 2000. 
        Web.  doi:10.1021/jp991723b.

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                    Carter, S, & Bowman, J M. Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential.  United States.  https://doi.org/10.1021/jp991723b

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                    Carter, S, and Bowman, J M. Thu .  
        "Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential".  United States.  https://doi.org/10.1021/jp991723b.

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@article{osti_20026893,

  title        = {Variational calculations of rotational-vibrational energies of CH{sub 4} and isotopomers using an adjusted ab initio potential},

  author       = {Carter, S and Bowman, J M},

  abstractNote = {The authors report variational calculations of vibrational energies of CH{sub 4}, CH{sub 3}D, CH{sub 2}D{sub 2}, CHD{sub 3}, and CD{sub 4} using the code Multimode and the ab initio force field of Lee and co-workers [Lee, T.J.; Martin, J.M.L.; Taylor, P.R.--J.Chem.Phys. 1995, 102, 254], re-expressed using Morse variables in the stretch displacements. Comparisons are made with experimental energies for CH{sub 4} with this potential, and then small adjustments are made to the potential to improve agreement with experiment for CH{sub 4}. Calculations for the isotopomers are done using the adjusted potential and compared with experiment. Additional vibrational energies and assignments not reported experimentally are also given for CH{sub 4} and the isotopomers. Exact rotational-vibrational energies of CH{sub 4} are also reported for J = 1.},

  doi          = {10.1021/jp991723b},

  url          = {https://www.osti.gov/biblio/20026893},
  journal      = {Journal of Physical Chemistry A: Molecules, Spectroscopy, Kinetics, Environment, amp General Theory},

  issn         = {1089-5639},

  number       = 11,

  volume       = 104,

  place        = {United States},

  year         = {2000},

  month        = {3}

}

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