Neutron diffraction of hole polaron ordering inLa1−xSrxMnO3(x≃18)

The polaron-ordered structure of ${\mathrm{La}}_{1-x}{\mathrm{Sr}}_x{\mathrm{MnO}}_3\hspace{0.5em}\left(x\cong \frac{1}{8}\right)$ has been reinvestigated to verify the previously proposed models. We found satellite reflections on the ${\mathrm{}(0,k,l)\mathrm{}}_{\mathrm{ortho}}$ and ${\mathrm{}(1,k,l)\mathrm{}}_{\mathrm{ortho}}$ reciprocal planes. It has been shown that neither of the previously proposed models is completely consistent with the observed results. Based on theoretical consideration of interhole interactions in a perovskite-based structure, the experimental results are analyzed. A polaron ordered structure with unit cell size of $(\sqrt{2}\times \sqrt{2}\times {4)}_{\mathrm{cubic}}$ has been proposed which is substantially consistent with the observed neutron-scattering pattern.