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Spatially dependent H-bond dynamics at interfaces of water/biomimetic self-assembled lattice materials.

ABSTRACT: Understanding hydrogen-bond interactions in self-assembled lattice materials is crucial for preparing such materials, but the role of hydrogen bonds (H bonds) remains unclear. To gain insight into H-bond interactions at the materials' intrinsic spatial scale, we investigated ultrafast H-bond dynamics between water and biomimetic self-assembled lattice materials (composed of sodium dodecyl sulfate and ?-cyclodextrin) in a spatially resolved manner. To accomplish this, we developed an infrared pump, vibrational sum-frequency generation (VSFG) probe hyperspectral microscope. With this hyperspectral imaging method, we were able to observe that the primary and secondary OH groups of ?-cyclodextrin exhibit markedly different dynamics, suggesting distinct H-bond environments, despite being separated by only a few angstroms. We also observed another ultrafast dynamic reflecting a weakening and restoring of H bonds between bound water and the secondary OH of ?-cyclodextrin, which exhibited spatial uniformity within self-assembled domains, but heterogeneity between domains. The restoration dynamics further suggest heterogeneous hydration among the self-assembly domains. The ultrafast nature and meso- and microscopic ordering of H-bond dynamics could contribute to the flexibility and crystallinity of the material--two critically important factors for crystalline lattice self-assemblies--shedding light on engineering intermolecular interactions for self-assembled lattice materials.

SUBMITTER: Wang H

PROVIDER: S-EPMC7519292 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Spatially dependent H-bond dynamics at interfaces of water/biomimetic self-assembled lattice materials.

Wang Haoyuan H Wagner Jackson C JC Chen Wenfan W Wang Chenglai C Xiong Wei W

Proceedings of the National Academy of Sciences of the United States of America 20200909 38

Understanding hydrogen-bond interactions in self-assembled lattice materials is crucial for preparing such materials, but the role of hydrogen bonds (H bonds) remains unclear. To gain insight into H-bond interactions at the materials' intrinsic spatial scale, we investigated ultrafast H-bond dynamics between water and biomimetic self-assembled lattice materials (composed of sodium dodecyl sulfate and β-cyclodextrin) in a spatially resolved manner. To accomplish this, we developed an infrared pum ...[more]

PMID: 32907936

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Spatially dependent H-bond dynamics at interfaces of water/biomimetic self-assembled lattice materials.

Publications

Spatially dependent H-bond dynamics at interfaces of water/biomimetic self-assembled lattice materials.

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