A study of the disorder in heavily doped Ba1-xLaxF2+x by neutron scattering, ionic conductivity and specific heat measurements

Niels Hessel Andersen, Kurt Nørgaard Clausen, Jørgen Kjems, J. Schoonman

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    The ionic disorder in single crystals of the fluorite-type solid solutions Ba1-xLaxF2+x (with x=0.209 and x=0.492) has been studied in the temperature range from room temperature to 800 degrees C by diffuse neutron scattering, ionic conductivity, and specific heat measurements. From the diffuse neutron scattering it was found that the disorder was dominated by 222 clusters, which at low temperatures (T>10-10s), in agreement with NMB results which suggest a jump frequency below 75 MHz. The temperatures at which the steepest slopes are found in the loss of correlations and in the conductivity coincide at approximately 650 degrees C. At this temperature no clear anomaly is observed in the specific heat. Based on these findings the authors propose a conduction mechanisms where F- ions are moving through the lattice by means of rearrangements of the 222 clusters.
    Original languageEnglish
    JournalJournal of Physics C: Solid State Physics
    Volume19
    Issue number14
    Pages (from-to)2377-2389
    ISSN0022-3719
    DOIs
    Publication statusPublished - 1986

    Fingerprint

    Dive into the research topics of 'A study of the disorder in heavily doped Ba1-xLaxF2+x by neutron scattering, ionic conductivity and specific heat measurements'. Together they form a unique fingerprint.

    Cite this