• Temperature variation of the Debye-Waller factors of Ba++ and F ions in BaF2 powder by x-ray diffraction

    • Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/pram/019/03/0203-0213

    • Keywords

       

      Cryostat; powder diffraction; Debye-Waller factor; lattice dynamics; barium fluoride

    • Abstract

       

      The temperature variation of the Debye-Waller factors of Ba++ and F ions in BaF2 powder has been studied using x-ray powder diffraction over the temperature range 77°–298°K. A continuous flow cryostat has been specially fabricated for this purpose for the YPC 50 NM powder diffractometer available in the department. The Debye-Waller factors of Ba++ and F between room temperature and 879°K have been measured using single crystal neutron diffraction by Cooperet al. Theoretical lattice dynamics shell model calculations using a 7-parameter model in a quasiharmonic approximation have been done over a temperature range 77° to 879°K. The theoretical values have been compared with the present x-ray measurements and the single crystal neutron diffraction values and the results are discussed.

    • Author Affiliations

       

      R Srinivasan1 K S Girirajan1 2

      1. Department of Physics, Indian Institute of Technology, Madras - 600,036, India
      2. Department of Crystallography and Biophysics, University of Madras, Guindy Campus, Madras - 600 025, India
    • Dates

       
  • Pramana – Journal of Physics | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2017-2019 Indian Academy of Sciences, Bengaluru.