有证据表明Au ((CN) ((2) ((-) 中存在显著的共价键
Xue-Bin Wang1, Yi-Lei Wang, Jie Yang
1Department of Physics, Washington State University, 2710 University Drive, Richland, Washington 99354, USA.
Journal of the American Chemical Society
|October 29, 2009
概括
这项研究揭示了黄金二化离子 (Au(CN) 2 -) 内黄金-碳键的显著共价键. 实验和计算方法证实了这种共价性质,解释了该化合物的非凡稳定性.
科学领域:
- 无机化学 无机化学
- 物理化学 物理化学
- 计算化学计算化学
背景情况:
- 金二化离子 (Au(CN) 2-) 是一种高度稳定的黄金化合物.
- 尽管它具有稳定性,但其化学结合的精确性质,特别是Au-C结合,仍然不完全理解.
研究的目的:
- 提供直接实验证据,证明Au(CN) 2-.的Au-C键中的共价键性质.
- 通过光谱和计算分析,阐明Au(CN) 2中的电子结构和化学键.
- 为了比较Au(CN) 2中的结合与其较轻的同类,Ag(CN) 2和Cu(CN) 2-.
主要方法:
- 使用118nm分离光子进行光电子光谱学.
- 与银二化物 (Ag(CN) 2-) 和铜二化物 (Cu(CN) 2-) 的实验比较.
- 密度函数理论 (DFT) 和高层次的初始计算.
主要成果:
- 观察在Au-C拉伸模式下所有脱离过渡的振动进展在Au(CN)2-.
- 与Cu(CN) 2 - - 所观察到的类似原子的转换形成鲜明对比,突出显示了Au(CN) 2 - - 中的共价键.
- 详细的电子结构信息获得了Au(CN)2-.
结论:
- 直接的实验证据证实,Au(CN) 2-. 的Au-C键具有显著的共价性.
- 相对论效应在Au(CN) 2-.中观察到的强共价键中起着至关重要的作用.
- 发现的共价键解释了黄金二化离子的异常稳定性.
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