在 (R) -(+) -1,1'-bi-2-naphthol二甲基乙醇纳米颗粒中的尺寸依赖激素奇拉性
Debao Xiao1, Wensheng Yang, Jiannian Yao
1Key Laboratory of Photochemistry and Laboratory of Organic Solids, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, P. R. China.
Journal of the American Chemical Society
|November 26, 2004
概括
有机纳米颗粒 (R) - - - +) - - 1′ - - 2′ - - 纳二甲基乙烯 (BNDE) 与溶液形式相比,显示出反向的激素奇拉性. 在奇拉纳米粒子中这种尺寸依赖现象是由于分子间激发合.
科学领域:
- 有机纳米粒子 有机纳米粒子
- 奇拉化学 奇拉化学
- 频谱学是一种光谱学.
背景情况:
- 状分子可以表现出独特的光学特性.
- 通过尺寸控制纳米粒子属性对于先进的应用至关重要.
- 循环二重化 (CD) 光谱是分析奇拉性的一个关键工具.
研究的目的:
- 为了制造有机纳米粒子从 (R) -(+) -1,1′-bi-2-naphthol二甲基乙醇 (BNDE).
- 为了研究BNDE纳米颗粒的尺寸依赖激发性.
- 为了阐明背后的基拉性逆转和光谱变化背后的机制.
主要方法:
- 纳米粒子合成的沉方法.
- 循环二极化 (CD),紫外线和光谱学.
- 激发状态寿命测量和量子力学计算.
主要成果:
- 已经成功合成了BNDE纳米粒子 (25-100nm).
- 纳米颗粒显示出积极的激素性,与稀释溶液相反.
- 刺激子性显示出一个尺寸依赖的红移,随着粒子大小的增加.
结论:
- 在BNDE纳米粒子中,性逆转是由分子间激子合引起的.
- 增加的分子间相互作用与更大的颗粒大小导致人染色变化.
- 粒子大小是一个关键因素,影响有机纳米颗粒的光学特性.
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