Calculated pressure induced electronic and structural transitions in transition metals

Abstract

The partial occupation numbers and the density of states (DOS) at the Fermi level were calculated as a function of reduced atomic volume for transition metals by employing the linear-muffin-tin-orbital (LMTO) method. The pressure induced electronic transitions from sp states to d states are confirmed for early metals; and for the heavier elements, on the otherhand, pressure induced d→p electronic transitions were found. By means of the abrupt changes obtained in the p-DOS values, good agreement with regard to experiment were found in predicting the structural phase transition volumes and it is concluded that the phase stability of transition metals under pressure is related to the characteristic shape of DOS near the Fermi level.

Keywords

• Pressure, occupation numbers, structural phase transitions, transition metals

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