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 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 β-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 β-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.

VSFG (vibrational sum frequency generation) microscopy was used to study the SDS@2β-CD system, a synthetic capsid-like self-assembled material. We found because of strong hydrogen-bond interactions between water and the assemblies, water molecules are template to adopt the local mesoscopic ordering of the self-assemblies, which allows VSFG to probe water on nonflat interfaces. We show that the origin of the VSFG signal from the self-assembly is a combination of individual molecular chirality and highly coordinated ordering of the self-assembly, which gives rise of anisotropic signals, e.g., under SSS polarization. A similar strategy could be applied to other self-assembled materials composed by molecules without inversion symmetry. Using an imaging process, VSFG spectra of different self-assembly sheets were spatially resolved. We found heterogeneity among different domains, which can be attributed to variations in the hydration level of different domains. Since the SDS@2β-CD system is a synthetic lattice self-assembly, such heterogeneity could also exist in other natural lattice assemblies such as a virus and tubulin.

We use transient XUV reflection absorption spectroscopy to study polaron formation on hematite and akaganeite surfaces. We observed a reduction in the offset of the imaginary refractive index (κoffset) that...