Effect of dilution on the spin pairing transition in rhombohedral carbonates
Effect of dilution on the spin pairing transition in rhombohedral carbonates
复制标题
稀释对菱面体碳酸盐自旋配对跃迁的影响
DOI：
10.1080/08957959.2010.485391
复制
发表时间：
2010
影响因子：
2
通讯作者：
G. Shen
中科院分区：
文献类型：
--
作者：
B. Lavina;P. Dera;R. Downs;O. Tschauner;Wenge Yang;O. Shebanova;G. Shen
通过单晶衍射测定了含铁菱镁矿的压缩率高达 64 GPa。在高达 49 GPa 的情况下，含有 12% Fe2+ 的固溶体的晶胞体积的压力演化可以通过参数为 V 0=281.0(5) Å3, K 0=102.8(3) GPa, K 的三阶 Birch-Murnaghan 状态方程来描述。 Fe2+ d 电子的自旋配对发生在 49 至 52 GPa 之间，不连续的体积变化证明了这一点。转变压力较铁端件提高约5GPa；与相邻簇对自旋跃迁的协同贡献一致的效应。然而，方镁石-方铁矿固溶体的趋势相反。讨论了两种结构之间的差异，特别是在 Fe-Fe 相互作用方面，这可能解释了不同的行为。
The compressibility of an iron-bearing magnesite was determined by means of single crystal diffraction up to 64 GPa. Up to 49 GPa the pressure-evolution of the unit cell volume of the solid solution with 12% of Fe2+ can be described by a third-order Birch–Murnaghan equation of state with parameters V 0=281.0(5) Å3, K 0=102.8(3) GPa, K . The spin pairing of the Fe2+ d-electrons occurs between 49 and 52 GPa, as evidenced by a discontinuous volume change. The transition pressure is increased by about 5 GPa compared with the iron end-member; an effect consistent with a cooperative contribution of adjacent clusters to the spin transition. The trend is, however, opposite in the periclase–wüstite solid solution. Differences among the two structures, in particular in the Fe–Fe interactions, that might explain the different behavior are discussed.