甲基胺-分子的结构和聚合,Me(n) H(3-n) N.BH(3) (n = 1-3),通过X射线衍射,气相电子衍射和量子化学计算进行研究
Simon Aldridge1, Anthony J Downs, Christina Y Tang
1Inorganic Chemistry Laboratory, University of Oxford, UK.
Journal of the American Chemical Society
|January 28, 2009
概括
用气相电子衍射和量子计算确定了氨基 adducts 的结构. 在甲基胺和二甲基胺-晶体中观察到二结合,揭示了关键的分子间相互作用.
科学领域:
- 无机化学 无机化学
- 结构化学 结构化学
- 计算化学计算化学
背景情况:
- 氨基添加物在各种化学应用中非常重要.
- 了解它们的结构对于预测它们的特性和反应性至关重要.
- 之前的研究已经描述了该系列的一些成员,但缺乏跨不同阶段的全面结构分析.
研究的目的:
- 为了阐明甲基胺-和二甲基胺-在气相中的分子结构.
- 为了确定甲基胺,二甲基胺和三甲基胺-的晶体结构.
- 研究分子间相互作用,特别是N-H...H-B二结合,以及它们对固态结构的影响.
主要方法:
- 气相电子衍射 (GED) 用于气相结构的确定.
- 量子化学计算来补充实验数据.
- 单晶X射线衍射用于固态结构的确定.
- 半经典密度和 (SCDS-PIXEL) 方法来评估二次相互作用.
主要成果:
- 甲基胺-和二甲基胺-的分子结构在气相中确定.
- 甲基胺,二甲基胺和三甲基胺-酸的晶体结构已成功解决.
- 在甲基胺和二甲基胺-的固态结构中发现了显著的N-H...H-B二键.
- 气态添加物的结构变化和能量与氨基片的基本性相关.
结论:
- 现在已对整个氨和氨系列 (n=0-3) 既在气相和固体相中的结构进行了全面的了解.
- 二键在这些附加物体的固态结构中起着至关重要的作用.
- 这项研究提供了对氨基系统中结构属性关系的基本见解.
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