Orbital ordering in La0.5Sr1.5MnO4 studied by model Hartree-Fock calculation

Article

关键词: TRANSITION-METAL OXIDES;    ELECTRONIC-STRUCTURE;    COLOSSAL MAGNETORESISTANCE;    DOUBLE EXCHANGE;    CHARGE;    LA1-XSRXMNO3;    PHYSICS;   

DOI  :  10.1103/PhysRevB.72.233104

来源: SCIE

【 摘 要 】

We have investigated orbital ordering in the half-doped manganite La0.5Sr1.5MnO4, which displays spin, charge, and orbital ordering, by means of unrestricted Hartree-Fock calculations on the multiband p-d model. From a recent experiment, it has become clear that La0.5Sr1.5MnO4 exhibits a cross-type (z(2)-x(2)/y(2)-z(2)) orbital ordering rather than the widely believed rod-type (3x(2)-r(2)/3y(2)-r(2)) orbital ordering. The calculation reveals that cross-type (z(2)-x(2)/y(2)-z(2)) orbital ordering results from an effect of in-plane distortion as well as from the relatively long out-of-plane Mn-O distance. For the Mn4+ site, it is shown that the elongation along the c axis of the MnO6 octahedra leads to an anisotropic charge distribution rather than the isotropic one.

【 授权许可】

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