关于被奇拉-连接物保护的金属纳米集群所显示的光学活动的起源
Ariadna Sánchez-Castillo1, Cecilia Noguez, Ignacio L Garzón
1Instituto de Física, Universidad Nacional Autónoma de México, Apartado Postal 20-364, 01000 México, DF, México.
Journal of the American Chemical Society
|January 22, 2010
概括
黄金集群上的奇拉尔配体会产生光学活动. 这项研究表明,这两个星团都存在.
科学领域:
- 计算化学和纳米科学
- 材料的光谱学和光学特性.
背景情况:
- 被联结体保护的金属集群可以显示光学活性,当使用奇拉分子作为保护联结体时.
- 这些纳米级材料中光学活动的现有理论包括奇拉集群核心,不对称场效应和奇拉足迹模型.
- 了解光学活动的起源对于设计功能性纳米材料至关重要.
研究的目的:
- 通过使用理论计算,研究谷氨保护的[Au(25)(SG)(18)](-) 集群中光学活动的物理化学起源.
- 阐明金属核心和体-金属结合模式对循环二元化 (CD) 频谱的贡献.
主要方法:
- 第一原则 循环二元化 (CD) 频谱的理论研究.
- 用氨酸保护的[Au(25)(SR(cys))(18)](-) 集群计算CD频谱.
- 分析电子结构和联体金属相互作用.
主要成果:
- 囊蛋白保护集群的计算CD频谱与谷氨保护集群的实验数据密切匹配.
- 扭曲的金属核心和特定的硫酸盐-黄金结合方式都对观察到的光学活动作出了贡献.
- 连接体的不对称排列增强了由核心扭曲引起的弱CD信号.
结论:
- 基拉-联结体保护的金属集群的光学活动源于多种机制的同时相互作用,而不是单一的主导机制.
- 酸盐连接体的方向和稳定性显著影响CD线形状和整体光学响应.
- 这项工作为管理金纳米集群光学活动的结构-属性关系提供了更深入的见解.
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