The dominant “heating” mode: bending excitation of water molecules by low-energy positron impact

Atomic and Molecular Collisions

Abstract.

We report a quantum dynamical treatment of the vibrational excitation of the bending mode of water molecules by collision with low energy positrons in the energy regions close to threshold openings. The exact vibrationally coupled-channel equations derived for the total e+-H2O system are solved in a Body-Fixed-Vibrational-Coupled-Channels (BF-VCC) reference frame, using a single-center expansion of the total wavefunction and of the interaction potential. The vibrationally inelastic cross-sections for transitions from the ground to the lowest excited state of the bending mode clearly show the bending excitation channel to be the dominant inelastic process at low collision energies. Comparisons with our earlier calculations for the other modes and for the excited processes induced by electron impact are also presented and analysed.

Keywords

Collision Energy Vibrational Excitation Early Calculation Inelastic Process Lower Excited State 

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References

  1. T.E. Cravens, A. Korosmezey, Planet Space Sci. 34, 961 (1986)CrossRefGoogle Scholar
  2. M.A. Ishii, M. Kimura, M. Inokuti, Phys. Rev. A 42, 6486 (1990) CrossRefPubMedGoogle Scholar
  3. N.J. Mason, W.M. Johnstone, P. Akther, Electron Collisions with Molecules, Clusters, and Surfaces, edited by H. Ehrhardt, L.A. Morgan (New York, Plenum, 1994), p. 47 Google Scholar
  4. I. Krajcar-Bronic, M. Kimura, J. Chem. Phys. 103, 7104 (1995)CrossRefGoogle Scholar
  5. G. Seng, F. Linder, J. Phys. B: At. Mol. Phys. 9, 2539 (1976)CrossRefGoogle Scholar
  6. T.W. Shyn, S.Y. Cho, T.E. Cravens, Phys. Rev. A 38, 678 (1988)CrossRefPubMedGoogle Scholar
  7. A.A.A. El-Zein, M.J. Brunger, W.R. Newell, J. Phys. B: At. Mol. Opt. Phys. 33, 5033 (2000)CrossRefGoogle Scholar
  8. M. Allan, O. Moreira, J. Phys. B: At. Mol. Opt. Phys. 35, L37 (2002)Google Scholar
  9. T. Nishimura, Y. Itikawa, J. Phys. B: At. Mol. Opt. Phys. 28, 1995 (1995)CrossRefGoogle Scholar
  10. O. Moreira, D.G. Thompson, B.M. McLaughlin, J. Phys. B: At. Mol. Opt. Phys. 34, 3737 (2001)CrossRefGoogle Scholar
  11. R. Curik, P. Carsky, J. Phys. B: At. Mol. Opt. Phys. 36, 2165 (2003)CrossRefGoogle Scholar
  12. T. Nishimura, F.A. Gianturco, Nucl. Inst. Meth. Phys. Res. B 221, 24 (2004)Google Scholar
  13. J.P. Sullivan, S.J. Gilbert, C.M. Surko, Phys. Rev. Lett. 86, 1494 (2001)CrossRefPubMedGoogle Scholar
  14. T. Nishimura, F.A. Gianturco, Europhys. Lett. 65, 179 (2004)CrossRefGoogle Scholar
  15. T. Nishimura, F.A. Gianturco, Phys. Rev. A 65, 062703 (2002)CrossRefGoogle Scholar
  16. T. Nishimura, F.A. Gianturco, J. Phys. B: At. Mol. Opt. Phys. 35, 2873 (2002)CrossRefGoogle Scholar
  17. Y. Itikawa, Int. Rev. Phys. Chem. 16, 155 (1997)CrossRefGoogle Scholar
  18. E.g. see: T.N. Rescigno, W.A. Isaacs, A.E. Orel, H.-D. Meyer, C.W. Mc Curdy, Phys. Rev. A 65, 032716 (2002)CrossRefGoogle Scholar
  19. N. Chandra, A. Temkin, Phys. Rev. A 13, 188 (1976)CrossRefGoogle Scholar
  20. E. Boronski, R.M. Nieminen, Phys. Rev. B 34, 3820 (1986)CrossRefGoogle Scholar
  21. N.T. Padial, D.W. Norcross, Phys. Rev. A 29, 1742 (1984)CrossRefGoogle Scholar
  22. W. Kohn, L.J. Sham, Phys. Rev. 140, A1133 (1965)Google Scholar
  23. F.A. Gianturco, A. Jain, Phys. Rep. 143, 347 (1986)CrossRefGoogle Scholar
  24. M.J. Frish et al., Gaussian 98, Revision A.7 (Pittsburg, PA: Gaussian Inc., 1998) Google Scholar
  25. W.N. Sams, D.J. Kouri, J. Chem. Phys. 51, 4809 (1969)CrossRefGoogle Scholar
  26. T.N. Rescigno, A.E. Orel, Phys. Rev. A 25, 2402 (1982)CrossRefGoogle Scholar
  27. W.F. Murphy, J. Chem. Phys. 67, 5877 (1977)CrossRefGoogle Scholar
  28. T. Shimanouchi, Tables of molecular vibrational frequencies consolidated, Vol. 1, National Standard Reference Data Series, National Bureau of Standards 39 (Washington, DC; US Goverment Printing Office, 1972), p. 10 Google Scholar
  29. I.G. John, G.B. Bacskay, N.S. Hush, Chem. Phys. 38, 319 (1979)CrossRefGoogle Scholar

Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2005

Authors and Affiliations

  1. 1.Department of Chemistry and INFM, The University of Rome “La Sapienza”RomaItaly

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