First-Principles Study of the High Pressure Phases of MnO and FeO
Abstract
The electronic structures and the phase stability of MnO and FeO under high-pressure were studied with the first-principles plane-wave basis pseudopotential calculations. The present calculations based on GGA account well for the properties of MnO and FeO especially in the high-pressure region. For the low pressure regime, where the electron correlation is very strong, we perform the LDA+U calculations to supplement the GGA results. Our results predict that the high-pressure phase of MnO should take the metallic normal NiAs (nB8) structure rather than the B2 structure, and that a metastable NM B1 structure can be realized for MnO in the intermediate pressure range. A very unique AF iB8 structure rather than the nB8 structure is predicted as the high-pressure phase of FeO. The novel feature of the AF iB8 FeO with the stoichiometric composition is that the system should be a band insulator in the ordered AF state and the existence of a band gap leads to special stability of this phase. Analysis of x-ray diffraction experiments provides a further support to the present theoretical prediction for both MnO and FeO.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 1998
- Bibcode:
- 1998APS..MAR.I3404F