Raman spectroscopy and theoretical modeling of BeO at high pressure

A. P. Jephcoat, R. J. Hemley, H. K. Mao, R. E. Cohen, M. J. Mehl

    Research output: Contribution to journalArticlepeer-review

    67 Citations (Scopus)

    Abstract

    The pressure dependence of the vibrational properties of BeO has been studied by Raman spectroscopy with a diamond-anvil, high-pressure cell. Five fundamental bands in the Raman spectrum were measured at room temperature for both a single crystal compressed with an argon medium to 41.5 GPa and a polycrystalline sample with no medium to 55 GPa. The frequencies of four modes [A1(TO), A1(LO), E1(TO), and E2] have a strong, positive pressure dependence, whereas that of the lowest-frequency mode (E2 symmetry at 338 cm-1) is weakly positive. No pressure-induced phase transitions were observed in BeO to the highest pressure of the experiments. These results are compared with parameter-free calculations using the potential-induced breathing (PIB) model. A transition from the wurtzite structure (B4) to the rocksalt structure (B1) is predicted at 40 GPa and is consistent with the experimental result since a pressure greater than the equilibrium transition pressure would be required to nucleate the B1 phase. The Raman frequencies and mode Gr̈neisen parameters calculated with PIB lattice dynamics agree closely with the experimental measurements.

    Original languageEnglish
    Pages (from-to)4727-4734
    Number of pages8
    JournalPhysical Review B
    Volume37
    Issue number9
    DOIs
    Publication statusPublished - 1988

    ASJC Scopus subject areas

    • Condensed Matter Physics

    Fingerprint

    Dive into the research topics of 'Raman spectroscopy and theoretical modeling of BeO at high pressure'. Together they form a unique fingerprint.

    Cite this