论文标题
使用$ 2p3d $ resonant noconant in弹性X射线散射揭示CO $ _ {3} $ $ $ $ $ _ {4} $的本地电子结构的网站选择性本地电子结构
Revealing the site selective local electronic structure of Co$_{3}$O$_{4}$ using $2p3d$ resonant inelastic X-ray scattering
论文作者
论文摘要
我们使用CO $ 2P3D $ resonant非弹性X射线散射（RIXS）调查了混合价氧化物CO $ _3 $ o $ $ _4 $。通过将共振边缘设置为CO $^{2+} $和CO $^{3+} $ ions，可以选择性地探测两个CO站点上的$ DD $激发，从而提供有关CO $ _3 $ o $ o $ o $ _4 $的本地电子结构的详细信息。 $ 23d $ rixs的结果揭示了$^4 $ t $ _ {2} $激发四面体CO $^{2+} $ site的激发状态，超出了光吸收光谱的判别能力。此外，$^3 $ t $ _ {2G} $兴奋时在1.3 eV处表示唯一地标识了八面体Co $^{3+} $站点。在群集多重模拟的指导下，Co $^{2+} $的基层字符和CO $^{3+} $ SITE被确定为高旋转$^4 $^4 $ a $ a $ _ {2} $（t $ _d $）和低速$^1 $^1 $ a $ a $ a $ _ {1g} $ $ $ $ _H $）。这表明只有Co $^{2+} $站点在Co $ _3 $ o $ $ _4 $的低温下是磁性活跃的站点。配体到金属电荷转移分析表明，在Co $^{3+} $站点的CO和O离子之间形成了强大的共价键，而Co $^{2+} $相当离子。
We investigate mixed-valence oxide Co$_3$O$_4$ using Co $2p3d$ resonant inelastic X-ray scattering (RIXS). By setting resonant edges at Co$^{2+}$ and Co$^{3+}$ ions, the $dd$ excitations on the two Co sites are probed selectively, providing detailed information on the local electronic structure of Co$_3$O$_4$. The $2p3d$ RIXS result reveals the $^4$T$_{2}$ excited state of tetrahedral Co$^{2+}$ site at 0.5 eV beyond the discriminative power of optical absorption spectroscopies. Additionally, the $^3$T$_{2g}$ excited stated at 1.3 eV is uniquely identified for the octahedral Co$^{3+}$ site. Guided by cluster multiplet simulations, the ground-state character of the Co$^{2+}$ and Co$^{3+}$ site is determined to be high-spin $^4$A$_{2}$(T$_d$) and low-spin $^1$A$_{1g}$(O$_h$), respectively. This indicates that only the Co$^{2+}$ site is magnetically active site at low-temperatures in Co$_3$O$_4$. The ligand-to-metal charge transfer analysis suggests a formation of a strong covalent bonding between Co and O ions at the Co$^{3+}$ site, while Co$^{2+}$ is rather ionic.
