尺寸选择的水性纳米滴中的离子:序列的水分子结合能和水对离子光效应的影响
William A Donald1, Ryan D Leib, Maria Demireva
1Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|October 18, 2011
概括
调查水的情况.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 纳米技术 纳米技术
背景情况:
- 了解离子水合对于各种化学和生物过程至关重要.
- 离子的光物理性质受到其周围溶剂分子的显著影响.
- 之前的研究已经探索了离子-水相互作用,但直接测量控制的纳米滴中的结合能是具有挑战性的.
研究的目的:
- 为了研究水对离子光效应的影响.
- 为了测量水分子对纳米滴中的水合离子的平均顺序结合能量.
- 为了确定纳米滴中的光物理性质是否模仿散装溶液中的光物理性质.
主要方法:
- 离子纳米热量计被用来测量结合能.
- 创建了含有特定离子 (罗达胺染料,Ce(3+),TrpH(+),[KYK + 2H](2+)) 和水分子的纳米滴.
- 用248nm的激发来诱导光,并记录了辐射波长.
主要成果:
- 纳米滴中的罗达胺染料和Ce(3+) 呈现出类似于散装溶液的光.
- 光量子收益率接近8个水分子≥8的纳米滴中的离子.
- 测定了水合离子的平均顺序水分子结合能,接近TrpH ((+) 和[KYK + 2H] ((2+) 的非对称值.
结论:
- 纳米滴中的离子的光物理特性接近于相对较小的集群大小的完全水合离子的光物理特性.
- 离子纳米热量计为研究离子-水相互作用和结合能提供了一种敏感的方法.
- 这些发现表明,在这些控制的纳米滴环境中,水具有类似液体的结构.
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