多不和二碳酸盐连接双氧化还原和染色体中心:吸收光谱和电子结构
F Albert Cotton1, James P Donahue, Carlos A Murillo
1Department of Chemistry, Laboratory for Molecular Structure and Bonding, P.O. Box 30012, Texas A&M University, College Station, Texas 77842-3012, USA. cotton@tamu.edu
Journal of the American Chemical Society
|May 2, 2003
概括
莫2化合物的颜色取决于二碳酸链接剂. 不和的链接器会导致强烈的颜色和较低的能量吸收,这是由于金属到配体的电荷转移过渡.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 金属有机化合物表现出不同的光学特性.
- 2核是一个已知的染色体.
- 双碳酸盐链接器可以调整材料属性.
研究的目的:
- 为了研究二碳酸盐结合剂对[Mo(2) ((DAniF) ((3))) ((O(2) CXCO ((2)) ((Mo(2) ((DAniF) ((3))) 化合物的吸收光谱的影响.
- 为了将链接器中的结构变化与观察到的颜色变化和电子转换相关联.
- 通过计算方法阐明负责观察到的颜色的电子激发.
主要方法:
- 吸收光谱法用于测量合成化合物的光谱.
- 进行了静态和时间依赖的密度函数理论 (DFT) 计算.
- 分析电子转换及其与分子结构的关系.
主要成果:
- 吸收光谱显示,对二碳氧化物链接剂的化学性质有很强的依赖.
- 不和二碳酸盐链接剂导致更强烈的颜色和更低的能量吸收.
- 对于不和链体,最低的能量吸收被确定为Mo(2)(4+) delta -->二碳酸盐pi金属到联体电荷转移过渡.
- 和的链接器导致了与非相互作用的Mo{2}{4}+) 染色体的delta -->delta过渡.
结论:
- 双碳酸盐连接器在确定这些Mo(2) 化合物的颜色和电子性质方面发挥着至关重要的作用.
- 链接器的性质 (和和不和) 决定了对观察到的颜色负责的电子过渡的类型.
- DFT计算成功地确定了观察到的光谱特征的电子起源.
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