结构和多核固态NMR的高度双裂的金化物协调聚合物
Michael J Katz1, Pedro M Aguiar, Raymond J Batchelor
1Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada V5A 1S6.
Journal of the American Chemical Society
|March 16, 2006
概括
这项研究合成了一种新型的协调聚合物Pb(H2O) [Au(CN) 2 2 ,揭示了其二维板块结构和由于以为中心的异质性而具有独特的光学特性. 脱水改变了结构和对称性,这是固态NMR证实的.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
- 频谱学是一种光谱学.
背景情况:
- 协调聚合物提供可调节的结构和特性.
- 已知 (II) 和金 (I) 化物形成有趣的超分子组合.
- 了解结构属性关系对于材料设计至关重要.
研究的目的:
- 合成和表征一种含有 (II) 和金 (I) 化物的新协调聚合物.
- 为了研究脱水后的结构变化.
- 探索合成材料的光学特性,特别是双折射.
主要方法:
- 通过KAu (CN) 2和Pb (NO3) 2的反应合成Pb (H2O) [Au (CN) 2].
- 单晶X射线衍射用于水合形式的结构性确定.
- 固态核磁共振 (NMR) 光谱 (13C,15N,1H,207Pb) 用于和脱水的形式.
- 进行X射线粉末衍射和双折度测量.
主要成果:
- 化化合物Pb(H2O) [Au(CN) ]22表现出1D链,形成2D板块,具有双盖三角形形体几何.
- 在175°C的脱水产生微晶Pb[Au(CN) 2) 2与改变的对称性和一个被提议的扭曲的正方形 prismatic ((II) 环境.
- 液化形式显示显著的双折度 (7.0 x 10^-2),归因于异型二维板块和对齐的CN键.
结论:
- 协调聚合物Pb(H2O) [Au(CN) ]2具有独特的二维分层结构,具有显著的光学异构性.
- 脱水导致结构和对称性变化,由固态NMR证明.
- 该材料的大双断率表明了在光学材料中的潜在应用.
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