用氧K边缘光谱学和电子结构理论评估金属氧多重键的共价性
Stefan G Minasian1, Jason M Keith, Enrique R Batista
1Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
Journal of the American Chemical Society
|January 29, 2013
概括
过渡金属氧离子中的金属氧结合是材料创新的关键. 新的研究揭示了电子结构如何在各组和下三位一体之间发生变化,影响金属-氧相互作用.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 生物化学 生物化学
- 无机化学 无机化学 有机化学
背景情况:
- 金属与氧的结合理论对于理解金属的氧性质至关重要.
- 过渡金属四氧化金属离子 (MO4(x-)) 的光谱分析历来为MO结合理论提供了信息.
研究的目的:
- 为了评估金属氧 (M-O) 轨道混合的相对变化,在四氧甲酸盐离子中.
- 调查6组和7组的M-O结合趋势以及向下过渡金属三合体.
主要方法:
- 非共振无弹性X射线散射 (NIXS).
- 通过光和扫描传输X射线显微镜 (STXM) 进行X射线吸收光谱 (XAS).
- 时间依赖密度函数理论 (TD-DFT) 的计算.
主要成果:
- 当从第6组转移到第7组或向下转换金属三元体时,观察到增加的MOe* (π*) 轨道混合.
- 与 (CrO42-) 相比, (ReO4-) 的混合量增加了一倍以上.
- 在t2*轨道 (σ* + π*) 中的混合在组内保持不变,但从6组增加到7组.
结论:
- 轨道能量和构成中异电子四氧化酸盐中的意想不到的变化与周期性趋势相关.
- 这些发现有助于我们更好地了解M-O结合及其对金属氧性质的影响.
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