超级交换和顺序机制负责在捐赠者和接受者之间与中介国家进行转移
Basil Pavlatos Paulson1, John R Miller, Wei-Xing Gan
1Chemistry Division, Argonne National Laboratory, Argonne, IL 60439, USA.
Journal of the American Chemical Society
|March 31, 2005
概括
当不和物质被引入纳-双分子的类固醇间隔器时,分子内电荷转移率显著增加. 超级交换在高中间能量时占主导地位,而顺序转移在低中间能量时占主导地位.
科学领域:
- 有机化学 有机化学
- 物理化学 物理化学
- 分子生物物理学 分子生物物理学
背景情况:
- 分子内电荷转移 (ICT) 在各种化学和生物过程中至关重要.
- 类固醇框架为研究ICT机制提供了多功能间隔器.
- 了解ICT是设计新型电子和光物理材料的关键.
研究的目的:
- 调查类固醇间隔器中不和对双和甲部分之间的ICT速率的影响.
- 在ICT中区分超级交换和顺序机制.
- 为了将ICT费率与中间国家的自由能源相关联.
主要方法:
- 在类固醇间隔器中合成不同程度不和的纳夫甲基-类固醇-双分子.
- 通过监测二基离子吸收的衰变来确定ICT速率.
- 超级交换和顺序电荷转移机制的计算建模.
主要成果:
- 随着类固醇间隔器中激素离子和离子不和度的增加,ICT率大幅增加.
- 对于的速率增强因子明显高于阴离子.
- 观察到,占主导地位的ICT机制明显依赖中间国家的自由能量.
结论:
- 类固醇间隔器中的不和增加了分子内电荷转移率.
- 超级交换是ICT的主要机制,当中介状态自由能源很大时.
- 当中间状态的自由能量很小时,顺序的电荷转移成为主导.
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