揭示了tris ((hexafluoroacetylacetonato) 铁 ((III) 的两个多态修饰:这是其他三价金属的常见情况吗?
Joyce Chang1, Julianna N Defeo1, Zheng Wei1
1Department of Chemistry, University at Albany, Albany, New York 12222, USA.
Acta crystallographica. Section C, Structural chemistry
|August 19, 2024
概括
铁三) 六酸乙酸,Fehfac) 3的识别已经得到了澄清. 这个复合体存在于两种不同的晶体形式,通过X射线衍射和热分析确定.
科学领域:
- 无机化学 无机化学 有机化学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 精确识别关键试剂在化学合成和研究中至关重要.
- 铁 (III) 六乙烯基酸盐,Fe (hfac) 3是重要的起始材料,其晶体形式一直是模两可的.
研究的目的:
- 解决长期存在的关于正确识别和表征铁 (III) 六乙烯基酸,Fe (hfac) 3.的问题.
- 调查Fe的不同晶体多态体的存在和特性3.
主要方法:
- 单晶X射线衍射以确定晶体结构.
- 粉末X射线衍射 (PXRD) 用于相位识别.
- 不同扫描热量计 (DSC) 和点测量用于热分析.
- 在实时质谱 (DART-MS) 和减弱总反射 (ATR) 谱学中进行直接分析,用于比较分析.
主要成果:
- Fe(hfac) 3以两种多态变异结晶:一种低温单临床形式 (1-L,P21/n) 和一种高温三角形形式 (1-H,P-3).
- 在44°C的升华过程中,低温多态 (1-L) 转化为高温多态 (1-H).
- PXRD,DSC和点测量清楚地区分了这两个多态体,而DART-MS,ATR光谱和物理特性显示了相似之处.
结论:
- 该研究成功地解决了Fe ((hfac) 3的识别问题,通过表征其两个不同的多态.
- 这些发现表明,多态性是一种常见的,但往往未被记录的,三价金属六乙烯基酸盐的现象,影响了它们在各种应用中的使用.
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