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 journalArticle

42 Citations (Scopus)

Abstract

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
Volume109
Issue number7
DOIs
Publication statusPublished - Aug 16 2012
Externally publishedYes

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crystal structure
atoms
boron
x ray diffraction
diffraction patterns
configurations
cells
metals
temperature

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Kolmogorov, A. N., Shah, S., Margine, E. R., Kleppe, A. K., & Jephcoat, A. P. (2012). Pressure-driven evolution of the covalent network in CaB 6 . Physical Review Letters, 109(7), [075501]. https://doi.org/10.1103/PhysRevLett.109.075501

Pressure-driven evolution of the covalent network in CaB 6 . / Kolmogorov, A. N.; Shah, S.; Margine, E. R.; Kleppe, A. K.; Jephcoat, A. P.

In: Physical Review Letters, Vol. 109, No. 7, 075501, 16.08.2012.

Research output: Contribution to journalArticle

Kolmogorov, AN, Shah, S, Margine, ER, Kleppe, AK & Jephcoat, AP 2012, 'Pressure-driven evolution of the covalent network in CaB 6 ', Physical Review Letters, vol. 109, no. 7, 075501. https://doi.org/10.1103/PhysRevLett.109.075501
Kolmogorov AN, Shah S, Margine ER, Kleppe AK, Jephcoat AP. Pressure-driven evolution of the covalent network in CaB 6 . Physical Review Letters. 2012 Aug 16;109(7). 075501. https://doi.org/10.1103/PhysRevLett.109.075501
Kolmogorov, A. N. ; Shah, S. ; Margine, E. R. ; Kleppe, A. K. ; Jephcoat, A. P. / Pressure-driven evolution of the covalent network in CaB 6 . In: Physical Review Letters. 2012 ; Vol. 109, No. 7.
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