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Joseph M Sperling¹, Evan J Warzecha¹, Cristian Celis-Barros¹

¹Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA.

|July 17, 2020

概括

高压通过增加5f轨道卷入,显著增强-硫键的共价性. 这个研究揭示了压力

科学领域:

协调化学
高压物理
乙化物化学

背景情况:

的独特半充满的5f外通常使其无氧化和抵抗5f轨道的结合.
金属呈现压力诱导的从局部到流动的5f电子的转变,影响其晶体结构.
压力对边界金属轨道的作用和 (III) 联体相互作用的共价性在很大程度上仍未被研究.

研究的目的:

研究 (III) - 连接物相互作用的压力依赖性修饰,特别关注 - 硫键.
通过改变5f/6d轨道的作用来确定高压是否可以诱导-联体键的共价性.
将-硫结合的压力效应与-氧结合和类似的化物化合物进行比较.

主要方法:

在高压下 (高达11GPa) 进行[Cm(pydtc) 4−的试验光谱研究.
计算证据分析轨道对金属连接体的贡献的变化.
在压力下对[Nd(pydtc) 4−和Cm(III) 的比较光谱分析.

主要成果:

高压可显著增强金属轨道对[Cm(pydtc) 4−中的-硫键的贡献.
5f轨道在-硫结合中的参与在0到11 GPa之间增加了一倍.
对于[Nd(pydtc) 4−和Cm(III) 合物,观察到较小的光谱变化,表明它们各自的键的扰动较小.

结论:

压力可以显著调节化合物的电子结构和结合特性.
这项研究表明,即使对于同一个离子来说,行为的协同性也是复杂的,并且依赖于压力.
这些发现为选择配体提供了指导,以探索压力对动因化合物的影响,并可能调整其性质.

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