School of Chemistry, The University of Sydney, Sydney, New South Wales, Australia.
J Phys Condens Matter. 2011 Nov 2;23(43):435401. doi: 10.1088/0953-8984/23/43/435401. Epub 2011 Oct 13.
Neutron diffraction methods are used to refine the structure of SrRu(0.8)Ni(0.2)O(3) at room temperature and 4 K. X-ray absorption measurements at the Ru L-edge demonstrate that partial oxidation of the Ru(4+) to Ru(5+) occurs upon introducing Ni into the SrRuO(3) structure to form SrRu(0.8)Ni(0.2)O(3). Whilst the diffraction measurements show that SrRu(0.8)Ni(0.2)O(3) is isostructural with SrRuO(3), the Ni doped compound exhibits an unusual first order orthorhombic-cubic phase transition near 670 K as revealed by x-ray diffraction. The Curie temperature in SrRu(0.8)Ni(0.2)O(3) is lower than that found in SrRuO(3) as a consequence of local distortions reducing the p-d hybridization.
中子衍射方法被用于在室温及 4 K 下对 SrRu(0.8)Ni(0.2)O(3)的结构进行细化。在 Ru L 边缘的 X 射线吸收测量表明，在 SrRuO(3)结构中引入 Ni 形成 SrRu(0.8)Ni(0.2)O(3)时，部分 Ru(4+)被氧化为 Ru(5+)。尽管衍射测量表明 SrRu(0.8)Ni(0.2)O(3)与 SrRuO(3)具有同构结构，但掺杂 Ni 的化合物在 670 K 附近表现出不寻常的一阶正交-立方相转变，这一点通过 X 射线衍射得到了揭示。由于局部畸变降低了 p-d 杂化，SrRu(0.8)Ni(0.2)O(3)的居里温度低于 SrRuO(3)。
