Numéro |
J. Phys. Colloques
Volume 42, Numéro C5, Octobre 1981
ICIFUAS-7Seventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids |
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Page(s) | C5-683 - C5-688 | |
DOI | https://doi.org/10.1051/jphyscol:19815105 |
ICIFUAS-7
Seventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids
J. Phys. Colloques 42 (1981) C5-683-C5-688
DOI: 10.1051/jphyscol:19815105
Laboratoire Dynamique Cristalline e t Uttrasons, D.R.P., Tour 22, Université Pierre et Marie Curie, 4, place Jussieu, 75230 Paris Cedex 05, France
Seventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids
J. Phys. Colloques 42 (1981) C5-683-C5-688
DOI: 10.1051/jphyscol:19815105
ULTRASONIC ABSORPTION IN SOME HIGHLY ATTENUATING IONIC-MOLECULAR CRYSTALS
F. Michard et F. PlicqueLaboratoire Dynamique Cristalline e t Uttrasons, D.R.P., Tour 22, Université Pierre et Marie Curie, 4, place Jussieu, 75230 Paris Cedex 05, France
Abstract
Unusually high values of the ultrasonic absorption observed at frequencies below 1 GHz in some ionic-molecular crystals the strontium, baryum and lead nitrates is a consequence of the existence of complex ions in the lattice. Acousto-optical interaction performed in the frequency range 0.1 GHz - 1 GHz and completed by data obtained at about 20 GHz by Brillouin scattering, allowed a very complete study from room temperature to 4 K of the dynamics of energy transfer between coupled internal and external vibrational modes in these compounds.