Abstract
Single-molecule imaging is challenging but highly beneficial for investigating intermolecular interactions at the molecular level1-6. Van der Waals interactions at the sub-nanometre scale strongly influence various molecular behaviours under confinement conditions7-11. Inspired by the traditional compass12, here we use a para-xylene molecule as a rotating pointer to detect the host-guest van der Waals interactions in the straight channel of the MFI-type zeolite framework. We use integrated differential phase contrast scanning transmission electron microscopy13-15 to achieve real-space imaging of a single para-xylene molecule in each channel. A good correlation between the orientation of the single-molecule pointer and the atomic structure of the channel is established by combining the results of calculations and imaging studies. The orientations of para-xylene help us to identify changes in the van der Waals interactions, which are related to the channel geometry in both spatial and temporal dimensions. This work not only provides a visible and sensitive means to investigate host-guest van der Waals interactions in porous materials at the molecular level, but also encourages the further study of other single-molecule behaviours using electron microscopy techniques.
Original language | English (US) |
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Pages (from-to) | 541-544 |
Number of pages | 4 |
Journal | Nature |
Volume | 592 |
Issue number | 7855 |
DOIs | |
State | Published - Apr 21 2021 |
Bibliographical note
KAUST Repository Item: Exported on 2021-04-27Acknowledged KAUST grant number(s): FCC/1/1974-16-01
Acknowledgements: We thank Q. Zhang and W. Gao for discussions. This work was supported by the National Key Research and Development Program of China (2018YFB0604801), the National Natural Science Foundation of China (21771029, 202013981 and 22005170) and the National Key R&D Program of China (2017YFB0602204). Y.H. thanks the Center Applied Research Fund (FCC/1/1974-16-01) from King Abdullah University of Science and Technology. We thank the Tsinghua National Laboratory for Information Science and Technology for assistance with the energy simulation.
ASJC Scopus subject areas
- General