Intermetallic charge-transfer transition in Bi1-xLaxNiO3 as the origin of the colossal negative thermal expansion
Intermetallic charge-transfer transition in Bi1-xLaxNiO3 as the origin of the colossal negative thermal expansion
复制标题
DOI：
10.1103/physrevb.88.014112
复制
发表时间：
2013-07-29
影响因子：
3.7
通讯作者：
Azuma, Masaki
中科院分区：
文献类型：
--
作者：
Oka, Kengo;Mizumaki, Masaichiro;Azuma, Masaki
利用中子粉末衍射 (NPD) 和 X 射线吸收光谱技术研究了三斜相到斜方相变的性质（在此过程中观察到巨大的负热膨胀）以及 Bi1-xLaxNiO3 的磁有序性。证实了从(Bi/La)3+0.5Bi0.55+Ni2+O3到(Bi/La)3+Ni3+O3的电荷转移转变的存在，并伴随着同时的结构变形。 NPD 数据还表明，磁有序仅存在于绝缘三斜相中。人们发现金属斜方相在温度低至 10 K 时仍是非磁性的。
The nature of triclinic to orthorhombic phase transition, at which colossal negative thermal expansion is observed, and the magnetic ordering of Bi1-xLaxNiO3 have been investigated with neutron powder diffraction (NPD) and x-ray absorption spectroscopy techniques. The presence of a charge-transfer transition from (Bi/La)3+0.5Bi0.55+Ni2+O3 to (Bi/La)3+Ni3+O3, accompanied by the simultaneous structural distortion, was confirmed. The NPD data also revealed that magnetic ordering is present only in the insulating triclinic phase. The metallic orthorhombic phase was found to be nonmagnetic down to 10 K.