在三价乙化物和兰坦化物离子复合体中的共价性比较
1Chemistry Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA. mjensen@anl.gov
Journal of the American Chemical Society
|August 15, 2002
概括
在液体-液体提取过程中,二甲二四三乙烯酸对三价性活性化物具有较高的选择性,而不是丁化物. 这种选择性来自于独特的协调化学,形成中性双酸复合体,没有内部球体水或酸盐.
科学领域:
- 在f元素的协调化学.
- 分离科学 分离科学
- 放射化学 放射化学是指辐射化学.
背景情况:
- 三价乙化物和化物离子在化学上是相似的,这给分离带来了挑战.
- 二甲二,四,四三甲二) 酸衍生物用于液体液体提取.
- 了解带协调是选择性分离的关键.
研究的目的:
- 为了研究含有f元素的酸盐,单酸盐和二酸盐连接体的协调模式.
- 阐明驱动dithiophosphinate对动因子的选择性的化学相互作用.
- 为了比较actinide和lanthanide复合物的结构性质.
主要方法:
- 可见吸收光谱学可见吸收光谱学
- 测量X射线吸收细结构 (XAFS) 测量
- 在n-多德干中研究Am(III),Cm(III),Nd(III) 和Sm(III) 复合物.
主要成果:
- 酸盐连接体以键二极体 (M(HL2)3) 的形式协调.
- 单基酸盐连接物通过氧和/或硫结合,作为双酸盐或单酸盐.
- 滴酸盐连接物形成中性双酸复合物 (ML3),没有内球酸盐或水.
- XAFS数据显示,类似大小的活性化物和化物离子的结构和键距离无法区分.
结论:
- 滴酸盐连接体对三价性活性化物的选择性源于其协调模式,形成中性双质复合体.
- 尽管有结构上的相似之处,但协调的微妙差异导致了动因类选择性.
- 这项研究提供了对选择性f元素分离机制的见解.
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