在MO (n) - 和MO (n) 集群 (M = Mo,W;n = 3-5) 中的电子结构和化学结合:光电子光谱学和ab initio研究
Hua-Jin Zhai1, Boggavarapu Kiran, Li-Feng Cui
1Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|December 9, 2004
概括
和氧化物集群 (MO ((n) -)) 显示出不同的电子结构. MO3-表现出稳定的封闭外配置,而MO4-和MO5-显示出由于氧-2p轨道的高电子结合能.
科学领域:
- 无机化学 无机化学 无机化学
- 物理化学 物理化学
- 计算化学是一种计算化学.
背景情况:
- 研究过渡金属氧化物的电子特性对于理解它们的反应性和稳定性至关重要.
- 和氧化物是具有多种应用的重要材料.
研究的目的:
- 为了阐明和氧化物集群的电子和结构演变 (MO(n) -, n=3-5).
- 为了全面理解,将实验观测与理论计算相关联.
主要方法:
- 用光电子谱学 (PES) 来探测MO{n}-离子的电子结构.
- 为了进行理论分析,进行了ab initio计算,包括密度函数理论和合集群单元,双元和三元[CCSD(T) 计算.
主要成果:
- 对于 (W) 和 (Mo) 氧化物集群,观察到类似的PES光谱.
- MO3-集群显示出一个大的能量差距,表明一个稳定的封闭中性物种.
- MO4和MO5星团表现出来自氧-2p轨道的高电子结合能 (>5.0 eV).
- 计算显示WO3是封闭外分子,WO4是三重基态物种,WO5是电荷转移复合体.
结论:
- 和氧化集群的电子结构和稳定性随着氧含量增加而显著演变.
- 实验 PES 数据和理论计算为这些集群的电子和结构性质提供了一致的图像.
- WO4和WO5具有独特的激进字符,突出其独特的电子配置.
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