Max Planck Institute for Intelligent Systems , D-70569 Stuttgart, Germany.
Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University , Atlanta, Georgia 30322, United States.
J Am Chem Soc. 2016 May 4;138(17):5495-8. doi: 10.1021/jacs.6b00958. Epub 2016 Apr 19.
We show hierarchical assembly of plasmonic toroidal metamolecules that exhibit tailored optical activity in the visible spectral range. Each metamolecule consists of four identical origami-templated helical building blocks. Such toroidal metamolecules show a stronger chiroptical response than monomers and dimers of the helical building blocks. Enantiomers of the plasmonic structures yield opposite circular dichroism spectra. Experimental results agree well with the theoretical simulations. We also show that given the circular symmetry of the structures s distinct chiroptical response along their axial orientation can be uncovered via simple spin-coating of the metamolecules on substrates. Our work provides a new strategy to create plasmonic chiral platforms with sophisticated nanoscale architectures for potential applications such as chiral sensing using chemically based assembly systems.
我们展示了等离子体环形超分子结构的分级组装，它们在可见光谱范围内表现出定制的旋光活性。每个超分子结构由四个相同的折纸模板螺旋构建块组成。与螺旋构建块的单体和二聚体相比，环形超分子结构表现出更强的手性光学响应。手性结构的对映体产生相反的圆二色光谱。实验结果与理论模拟吻合较好。我们还表明，给定结构的圆对称性，可以通过在基底上简单旋涂超分子结构来揭示其沿轴向的独特手性光学响应。我们的工作为使用基于化学的组装系统进行手性传感等潜在应用创造具有复杂纳米结构的等离子体手性平台提供了一种新策略。
