了解和预测中性复合体的扭曲的T-对Y几何,这些复合体由固态加重的β-diketiminate连接体支
Hongjun Fan1, Debashis Adhikari, Anas A Saleh
1Department of Chemistry, the Molecular Structure Center, and School of Informatics, Indiana University, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|November 28, 2008
概括
这项研究详细介绍了新的三坐标 (II) 复合体. 协调几何形状,T形或Y形,取决于连接体的电子特性,影响未来的催化剂设计.
科学领域:
- 无机化学 无机化学
- 有机金属化学 有机金属化学
- 协调化学 协调化学
背景情况:
- 三坐标,高旋转的金属复合物很少见,对于理解结合和反应性很重要.
- (NACNAC) 连接体系统为稳定异常的协调数和氧化状态提供了一个强大的平台.
研究的目的:
- 合成和描述新型的三坐标 (II) 复合物.
- 研究这些复合体的协调几何学 (T形与Y形) 规则的因素.
- 建立基于电子结构的理论框架,以预测基于电子结构的协调偏好.
主要方法:
- 通过盐转化合成合成 (II) 复合物.
- 使用单晶X射线衍射进行结构性表征.
- 使用密度函数理论 (DFT) 和分子轨道 (MO) 计算进行理论分析.
主要成果:
- 成功制备了一系列单核,中性三坐标 (II) 复合体,具有不同的配体 (L).
- 观察到复合体采用扭曲的T形或Y形几何,这取决于连接体L的性质.
- DFT和MO分析显示,pi捐赠的连接体更喜欢Y形几何学,而sigma捐赠的连接体更喜欢T形协调.
结论:
- 三坐标 (nacnac)Cr(II) 复合体的协调几何是由辅助联体的电子性质决定的.
- 在 (nacnac) Cr (II) 片段和连接体之间的边界轨道相互作用是几何学的关键决定因素.
- 这些发现提供了关于低坐标金属复合体中电子结构-联结物偏好关系的见解,这对Sc (II) 和Mn (II) 有影响.
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