The flexible architectural design of metal clusters and organic ligands attributes Metal-Organic Frameworks (MOFs) as one of the most versatile materials. Host-guest interactions contribute to this versatility, highlighting the need for a fundamental understanding of host frame-guest molecule units. Herein, ab-initio calculations elucidate the spatial distribution of H2O guest molecules (guests) within [101] honeycomb channel of Co-CUK-1, where the H2O guests are 1D aligned with the highest superposition density. In situ heating Raman spectroscopy demonstrates that H2O guests within the Co-CUK-1 frame behave like a vapor phase, maintaining phase stability even when heated to 120 °C. Scanning Transmission Electron Microscopy (STEM) enables the identification of both the Co-CUK-1 frame and the H2O guests in [101] honeycomb channel. Correlative Light and Electron Microscopy (CLEM) further reveals the intrinsic insulative nature of the Co-CUK-1 frame, along with extrinsic in-gap states caused by H2O adsorption. By integrating ab-initio calculations, in situ heating Raman spectroscopy, and atomic-scale investigations via STEM and CLEM, this study establishes a comprehensive structural analysis of MOFs-materials that are highly versatile yet extremely sensitive to electron beam exposure.
Keywords: ab‐initio calculations; channel‐orientation; in situ heating Raman spectroscopy; metal–organic frameworks; scanning transmission electron microscopy.
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