制备二元技术化物:TcBr3和TcBr4的制备
Frederic Poineau1, Efrain E Rodriguez, Paul M Forster
1Department of Chemistry, University of Nevada-Las Vegas, Las Vegas, Nevada 89154, USA. freder29@unlv.nevada.edu
Journal of the American Chemical Society
|January 1, 2009
概括
合成了新的技术化物,TcBr(3) 和TcBr(4). TcBr(3) 具有具有Tc-Tc债券的面部共享八面体链,而TcBr(4) 具有没有Tc-Tc债券的边缘共享八面体链.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 材料科学 材料科学 材料科学
背景情况:
- 技术 (Tc) 是一种罕见的过渡金属,已知化合物有限.
- 了解化的结构化学是探索其特性至关重要的.
研究的目的:
- 为了合成和表征新的甲化合物.
- 为了阐明技术三化物 (TcBr3) 和技术四化物 (TcBr4) 的晶体结构.
主要方法:
- 通过400°C的技术金属与的直接反应合成TcBr3和TcBr4.
- 单晶X射线衍射 (XRD) 用于详细的结构分析.
主要成果:
- TcBr3结晶在正方体空间组Pmmn中,具有无限链的共享面部TcBr6八面体,交替短和长Tc-Tc距离 (2.8283(4) Å和3.1434(4) Å).
- TcBr4结晶在正方体空间组Pbca中,包含无限链的边缘共享TcBr6八面体,没有明显的金属-金属键 (Tc-Tc = 3.7914(4) Å).
- TcBr3与RuBr3和MoBr3同型; TcBr4与PtBr4和OsBr4.4同型; TcBr4与PtBr4和OsBr4.4同型; TcBr4与RuBr3和MoBr3同型; TcBr4与PtBr4和OsBr4.4同型.
结论:
- TcBr3和TcBr4的合成和结构确定为技术的协调化学提供了新的见解.
- 在TcBr3和TcBr4中,独特的结构图案突出显示了石化对TcBr6八面体排列的影响,以及金属与金属结合的存在/不存在.
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