کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1491090 | 992342 | 2009 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Temperature evolution of structure and magnetic properties in the perovskite Sr2MnSbO6 Temperature evolution of structure and magnetic properties in the perovskite Sr2MnSbO6](/preview/png/1491090.png)
The structural and magnetic properties of the perovskite Sr2MnSbO6 have been studied. Combining neutron and X-ray powder diffraction data, the temperature evolution of the structural parameters was investigated with the Rietveld method between 2 and 1000 K. The crystal structure is tetragonal (space group I4/m) within the temperature interval of 2–750 K and cubic (space group Fm-3m) above 750 K. Both octahedral B-site positions were found to be partially occupied by Mn and Sb, but with different Mn/Sb ratios. The magnetic susceptibilities showed irreversibility between field cooled and zero-field cooled (ZFC) conditions and spin glass like magnetic dynamics including aging and memory phenomena at temperatures below 30 K; all appearing well above a broad maximum at 13 K in the ZFC susceptibility curves. This suggests that the material reaches an unconventional spin-glass state at low temperatures, possibly arising from a competitive situation between the double exchange (ferromagnetism) and the super-exchange (antiferromagnetism). Neutron diffraction patterns showed no evidence of a long-range magnetic ordering at 2 K which is consistent with spin glass behavior. The factors governing the observed structural and magnetic properties of Sr2MnSbO6 are discussed and compared with those of other quaternary Mn- and Sb-containing perovskites. Graphs of the temperature of magnetic phase transitions as functions of the cation size were constructed and are discussed for the AB3+1/2B5+1/2O3 series with isomorphous substitution of B3+ and B5+ cations. Possible influence of the A-cation sublattice on magnetic properties is also shortly considered.
Journal: Materials Research Bulletin - Volume 44, Issue 4, 2 April 2009, Pages 822–830