三角形双金字塔形或正方形平面形? 密度函数理论计算铁二 (dithiolene) N-异环碳化合物复合物的密度
Katherine Merkel1, Alyssa V B Santos1, Scott Simpson1
1Department of Chemistry, St Bonaventure University, St Bonaventure, NY 14778, USA. ssimpson@sbu.edu.
Dalton transactions (Cambridge, England : 2003)
|November 8, 2024
概括
密度函数理论 (DFT) 的计算显示,托尔曼电子参数 (TEP) 和百分比埋藏体积 (%Vbur) 最好预测铁 bis ((dithiolene) -N-异环碳酸盐 adducts 的协调几何.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学计算化学
- 协调化学 协调化学
背景情况:
- 铁双二甲基乙烯-N-异环碳素 (NHC) 添加物是一种协调复合物的类别,在催化和材料科学中具有潜在的应用.
- 了解控制它们协调几何学的因素对于设计具有特定性质的复合体至关重要.
- 之前的研究已经将电子和硬质参数与相关金属复合物的协调行为联系起来.
研究的目的:
- 调查各种电子和硬质参数对铁bis (dithiolene) -NHC adducts的协调几何学的预测能力.
- 确定影响Addison τ参数的关键参数,该参数区分正方形金字塔和三角形双金字塔几何.
- 建立强大的计算模型来预测这些复杂的协调偏好.
主要方法:
- 密度函数理论 (DFT) 的计算是对57个铁乙烯-NHC添加物进行的.
- 计算的参数包括核磁共振 (NMR) 化学转移 (13C,77Se,31P),托尔曼电子参数 (TEP),惠恩电子参数 (HEP) 和NHCs的百分比埋藏体积 (%Vbur).
- 使用多变量线性回归模型将这些参数与Addison τ参数相关联.
主要成果:
- 托尔曼电子参数 (TEP) 和NHC联体的百分比埋藏体积 (%Vbur) 的组合被确定为Addison τ值的最重要的预测因素.
- 这两个参数共同解释了协调几何学中相当大一部分差异.
- 包括额外的参数,如NMR化学转移和HEP,只为预测模型提供了边际的改进.
结论:
- 铁双乙烯-NHC附的协调几何主要是由与NHC连接体相关的电子 (TEP) 和硬质 (%Vbur) 因素的平衡决定的.
- TEP和%Vbur为预测这些复合体的协调偏好提供了一种可靠和可计算的方法.
- 这些发现为合理设计和合成具有定制结构和电子特性的铁-NHC复合体提供了宝贵的见解.
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