富勒伦体内的U-U键是真的不愿意的键吗?
Antonio Moreno-Vicente1, Yannick Roselló1, Ning Chen2
1Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcel·lí Domingo 1, Tarragona 43007, Spain.
Journal of the American Chemical Society
|March 6, 2023
概括
研究人员探索了二内金属 (EMF),发现强- (U-U) 三重键在较小的子中形成,如C60. 这些共价键挑战了古典的行为体化学假设.
科学领域:
- 无机化学
- 材料科学
- 量子化学
背景情况:
- 之前对二内体金属 (EMF) 的研究表明,与Th2@C80相比,U-U相互作用较弱.
- 经典的活性化物化学往往忽略了共价U-U键的可能性.
研究的目的:
- 研究在较小的二电磁场中形成共价U-U键的可行性.
- 了解各种富勒烯中的U-U结合的性质和强度.
主要方法:
- 双金属U2@C2n物种的激光消化合成 (2n ≥50).
- 质谱检测
- 密度函数理论 (DFT),CASPT2计算和分子动力学 (MD) 模拟.
主要成果:
- 在C60等较小中,成功形成具有强大的U{5f3}-U{5f3}三重键的二电磁场,其有效键顺序大于2.
- U-U键形成与U-相互作用竞争,影响晶体结构中的U-U距离.
- 显著的5f-5f轨道相互作用有助于约2.5 Å的共价键,在4 Å以上检测到额外的7s6d轨道重叠.
结论:
- 在较小的富勒烯中可以形成共价U-U三重键,这挑战了传统的活性化物化学.
- 电磁场中的金属离子作为形的模板而不是简单的封闭实体.
- 这项研究提供了关于在纳米碳结构中的结合特征的关键见解.
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