三/四的双酸复合物:一个隐藏的反氧活性联体的案例
David Samuvel Michael1, Georg Schreckenbach1
1Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada, R3T 2N2.
Inorganic chemistry
|May 15, 2024
概括
复合物与二 () - 化物联体表现出沉默的31PNMR光谱,这是由于基. 相对论DFT计算揭示了电子移位和U→L背接,表明这些氧化还原无害系统中的 (IV).
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学
- 计算化学的计算化学
背景情况:
- 已经合成了含有 bis () - 酸 (BAP) 连接体的复合物.
- 三 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二 () 二) 三 () 二 () 二 () 二 () 二 () 二) 三 () 二 () 二 () 二) 三 () 二 () 二 () 二 () 二 () 二) 三 () 二 () 二 () 二) 二 () 二二二二二二二二二二二四三二二二二二三二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二
- EPR光谱学表明,复合体2的连接体框架中有一个有机基.
研究的目的:
- 研究复合体1,2,4的电子结构.
- 了解复合体2的不寻常静音31P核磁共振频谱的起源.
主要方法:
- 相对论密度函数理论 (DFT) 的计算.
- 电子结构的分析,包括电子移位和背接.
- 对NMR和EPR光谱数据的解释.
主要成果:
- DFT计算显示了碳结合的减少和电子移位,表明了U→L的反向结合.
- 乙碳上的基基[OC•-]被确定为复合体2中的静音31PNMR光谱的原因.
- 在复合体2和4中,BAP连接体是氧化还原无毒的,导致正式的氧化状态为+4.
结论:
- BAP配体的氧化还原无害性解释了观察到的电子特性和NMR光谱.
- 基形成对于理解这些复合物的行为至关重要.
- 相对论DFT是阐明重元素化合物的电子结构的强大工具.
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