Pressure-driven evolution of the covalent network in CaB 6

A. N. Kolmogorov, S. Shah, E. R. Margine, A. K. Kleppe, A. P. Jephcoat

    Research output: Contribution to journalArticlepeer-review

    53 Citations (Scopus)


    We synthesized and solved an unexpectedly complex crystal structure of CaB 6 under high pressures (up to 44 GPa) and temperatures. The only known crystal structure in the large family of metal hexaborides, a simple cubic cP7 type discovered over 80 years ago, is shown here to transform into a tetragonal tI56 configuration comprised of unfamiliar 24-atom boron units. The interpretation of the convoluted x-ray diffraction pattern was accomplished with an ab initio evolutionary search which identified the tI56 structure (28 atoms per primitive unit cell) without any parameter input. The exotic CaB 6 phase was successfully quenched down to ambient pressure.

    Original languageEnglish
    Article number075501
    JournalPhysical Review Letters
    Issue number7
    Publication statusPublished - Aug 16 2012

    ASJC Scopus subject areas

    • Physics and Astronomy(all)


    Dive into the research topics of 'Pressure-driven evolution of the covalent network in CaB 6'. Together they form a unique fingerprint.

    Cite this