Redox-induced conformational change in mercaptoalkanoic acid multilayer films.
Redox-induced conformational change in mercaptoalkanoic acid multilayer films.
复制标题
氧化还原诱导的巯基链烷酸多层膜的构象变化。
DOI：
10.1021/la300510x
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Johnson S
中科院分区：
文献类型：
--
作者：
Johnson S
我们讨论了组装，结构和稳定性的多层分子膜形成的多个巯基链烷酸单分子膜连接通过羧基和巯基相互作用与二价铜离子。使用双偏振干涉测量研究组装的多层膜在真实的时间，我们观察到一个明确的线性关系的层数内的膜和整体的平均膜厚度。然而，出乎意料的是，我们发现了重组的较低的单层后，协会的Cu 2+离子形成的Cu羧酸盐表面。特别是，较低的单层的厚度被发现显着降低，伴随着膜密度的增加。随后恢复到原来观察到的构象的单层的铜离子还原为铜+后，化学吸附层。类似的重组也观察到在分子动力学模拟的双层膜组装在金表面上。我们结合实验和理论研究表明，所观察到的重组是相邻的铜离子之间的电荷-电荷相互作用的结果，存在于羧酸铜表面的+2氧化态和吸附层的化学吸附后的+1氧化态。
We discuss the assembly, structure, and stability of multilayer molecular films formed from multiple mercaptoalkanoic acid monolayers ligated via carboxyl and thiol interactions with divalent copper ions. Using dual-polarization interferometry to study the assembly of multilayer films in real time, we observe a clear linear relationship between the number of layers within a film and the overall average film thickness. Unexpectedly, however, we find a restructuring of the lower monolayer upon association of the Cu2+ions to form the Cu carboxylate surface. In particular, the thickness of the lower monolayer was found to decrease significantly, accompanied by an increase in the film density. The conformation of the monolayer subsequently recovered to that observed originally following the reduction of the Cu ion to Cu+upon chemisorption of the adlayer. Comparable restructuring was also observed in molecular dynamics simulations of a bilayer film assembled on a gold surface. Our combined experimental and theoretical study suggests that the observed restructuring is a result of charge–charge interactions between adjacent Cu ions that exist in the +2 oxidation state in the copper carboxylate surface and in the +1 oxidation state following chemisorption of the adlayer.
影响因子：
3.9
作者：
Riepl, M;Enander, K;Ortigao, F
通讯作者：
Ortigao, F