Theoretical structural phase stability of BeO to 1 TPa

The equation of state and structural phase stability of BeO have been calculated for pressures up to 1 TPa using two all-electron, full-potential electronic-structure techniques; one using a linear muffin-tin orbital basis and the other a linear combination of Gaussian type orbitals basis. Both methods predict an as yet unobserved series of phase transitions, wurtzite-->zinc blende-->rocksalt, with the final transition at about 95 GPa. This nearly exact local-density approximation result disagrees with all earlier, more approximate, calculations by at least 40%. A theoretical Hugoniot, consistent with shock wave data up to 100 GPa, has been generated for BeO using electronic-structure results.