Long Seminars (Abstracts)

  • Richard C. Powell
  • R. Englman
  • G. F. Imbusch
  • R. G. Pappalardo
  • Ferd Williams
Part of the NATO Advanced Study Institutes Series book series (NSSB, volume 8)


Investigations of the vibronic spectra of ions in crystals can be used to study the lattice dynamics of the host crystal and the effects caused by the interaction between the lattice phonons and the transition electron on the impurity ion. In this seminar we review the results of such studies of ions in strontium titanate crystals. This is an interesting host to study because of the presence of “soft” phonon modes which are responsible for the interesting dielectric properties and structural phase transitions of the material. Our recent work on SrTiO4:Cr3+ will be presented in detail as an example of a research project on vibronics. Most of the structure in the low energy vibronic sideband at low temperature can be identified using selection rules derived from group theory and comparing the results with those obtained from infrared absorption, Raman and neutron scattering. An iteration process was used to obtain a computer fit to the data from which one-phonon, two-phonon, and multi-phonon contributions to the sideband were derived. It was found that quadratic coupling between an impurity-induced local mode and the lattice phonon modes had to be included in order to obtain a fit. A very simple model is used to obtain a phonon density of states from the one-phonon vibronic sideband and this is found to agree fairly well with the density of states obtained from neutron scattering. The high energy vibronic sideband is shown to be useful in observing the low frequency phonons including the soft modes. The temperature dependences of the widths and positions of both the zero-phonon lines and the impurity-induced local mode are discussed in terms of the theoretical fittings predicted using a Debye phonon distribution, the effective phonon distribution obtained from the vibronic sideband, and an Einstein phonon distribution describing coupling to only a soft phonon mode.


Strontium Titanate Vibronic Spectrum Lead Azide Trivalent Actinide Soft Phonon Mode 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. (1).
    M.O. Henry (to be published).Google Scholar
  2. (2).
    M.O. Henry, et al., J. Phys. C. (1974), in press.Google Scholar
  3. (3).
    B. Di Bartolo and R. Peccei, Phys. Rev. 137A, 1770, (1965).CrossRefGoogle Scholar
  4. (4).
    B. Di Bartolo and R.C. Powell, Nuovo Cimento 66B, 21, (1970).ADSGoogle Scholar
  5. (5).
    B. Di Bartolo and G.F. Imbusch (to be published).Google Scholar
  6. (6).
    J.H. Parker, Jr., in Optical Properties of Ions in Crystals, edited by H.M. Crosswhite and H.W. Moos (Wiley, 1967).Google Scholar
  7. 1.
    M. Fred, Advances in Chemistry Series 71, l80 (1967).Google Scholar
  8. 2.
    B.G. Wybourne, Spectroscopic Properties of Rare Earths, John Wiley & Sons, New York, 1965.Google Scholar
  9. 3.
    W.T. Carnall and P.R. Fields, Advances in Chemistry Series 71, 86 (1967).Google Scholar
  10. 4.
    . R.G. Pappalardo, W.T. Carnall and P.R. Fields, J. Chem. Phys. 51, 1182 (1969).ADSCrossRefGoogle Scholar
  11. 5.
    W.T. Carnall, P.R. Fields and R.G. Pappalardo, J. Chem. Phys. 53, 2922 (1970).ADSCrossRefGoogle Scholar
  12. 6.
    W.T. Carnall, S. Fried and F. Wagner Jr., J. Chem. Phys. 58, 3614 (1973).ADSCrossRefGoogle Scholar
  13. 7.
    J.B. Gruber, J. Chem. Phys. 35, 2186 (l96l).CrossRefGoogle Scholar
  14. 8.
    W.F. Krupke and J.B. Gruber, J. Chem. Phys. 46, 542 (1967).ADSCrossRefGoogle Scholar
  15. 9.
    C.K. Jörgensen, R.G. Pappalardo and H.H. Schmidtke, J. Chem. Phys. 39, 1422 (1963).ADSCrossRefGoogle Scholar
  16. 10.
    R.G. Pappalardo, J. Mol. Spectros. 29, 13 (1969).ADSCrossRefGoogle Scholar
  17. 11.
    W.T. Carnall, P.R. Fields and R.G. Pappalardo, Proc. Intern. Conf. Coord. Chem. 11th, Haifa, Israel, Sept. 1968.Google Scholar
  18. 12.
    R. Pappalardo, W.T. Carnall and P.R. Fields, J. Chem. Phys. 51, 842 (1969).ADSCrossRefGoogle Scholar
  19. 13.
    R.A. Satten, D.J. Young and D.M. Gruen, J. Chem. Phys. 33, 1140 (1960).ADSCrossRefGoogle Scholar
  20. 14.
    R.G. Pappalardo and C.K. Jörgensen, Helv. Phys. Acta 37, 79 (1964).Google Scholar
  21. 15.
    R.A. Satten, C.L. Schreiber and E.Y. Wong, J. Chem. Phys. 42, 162 (1965).ADSCrossRefGoogle Scholar
  22. 16.
    I. Richman, P. Kisliuk and E.Y. Wong, Phys. Rev. 155, 262 (1967).ADSCrossRefGoogle Scholar
  23. 1.
    H. Fair and A. Forsyth, J. Phys. and Chem. Solids 30, 2559 (1969).ADSCrossRefGoogle Scholar
  24. 2.
    R. B. Hall and F. Williams, J. Chem. Phys. 58, 1036 (1973).ADSCrossRefGoogle Scholar
  25. 3.
    S. P. Varma, F. Williams and K. D. Möller, J. Chem. Phys. 60, 4950 (1974).ADSCrossRefGoogle Scholar
  26. 4.
    S. P. Varma and F. Williams, J. Chem. Phys. 60, 4955 (1974).ADSCrossRefGoogle Scholar
  27. 5.
    S. P. Varma and F. Williams, J. Chem. Phys. 59, 912 (1973).ADSCrossRefGoogle Scholar
  28. 6.
    J. Schanda, B. Baron and F. Williams, J. Luminescence (in press).Google Scholar

Copyright information

© Plenum Press, New York 1975

Authors and Affiliations

  • Richard C. Powell
    • 1
  • R. Englman
    • 2
  • G. F. Imbusch
    • 3
  • R. G. Pappalardo
    • 4
  • Ferd Williams
    • 5
  1. 1.Department of PhysicsOklahoma State UniversityStillwaterUSA
  2. 2.Soreq Nuclear Research CentreYavneIsrael
  3. 3.Department of PhysicsUniversity CollegeGalwayIreland
  4. 4.GTE Laboratories Inc.WalthamUSA
  5. 5.Department of PhysicsUniversity of DelawareNewarkUSA

Personalised recommendations