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Electronic structure and phase transition in polar ScFeO3 from First Principles Calculations

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 نشر من قبل Bog Kim
 تاريخ النشر 2016
  مجال البحث فيزياء
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The properties of newly discovered polar ScFeO3 with magnetic ordering are examined using Ab initio calculations and symmetry mode analysis. The GGA+U calculation confirms the stability of polar R3c Phase in ScFeO3 and the pressure induced phase transition to non-polar Pnma phase. Octahedron tilting and structural properties as a function of applied pressure have been analyzed. The origin of polar phase is associated with instability of non-polar R-3c phase and group theory using the symmetry mode analysis has been applied to understand this instability as well as the spontaneous polarization of polar R3c phase. The magnetic phase transition shows G-type AFM ordering of Fe3+ ion within Goodenough-Kanamori theory and the possibility of magnetic spin structure has been analyzed by using energy analysis including spin canting possibility.



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