Volume 62, Issue 35 e202305985
Research Article

Locating Hydrogen Positions for COF-300 by Cryo-3D Electron Diffraction

Wenjia Sun

Wenjia Sun

College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871 P.R. China

These authors contributed equally to this work.

Search for more papers by this author
Pohua Chen

Pohua Chen

College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871 P.R. China

These authors contributed equally to this work.

Search for more papers by this author
Mingxuan Zhang

Mingxuan Zhang

College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871 P.R. China

Search for more papers by this author
Jian-Xin Ma

Jian-Xin Ma

College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871 P.R. China

Search for more papers by this author
Prof. Dr. Junliang Sun

Corresponding Author

Prof. Dr. Junliang Sun

College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871 P.R. China

Search for more papers by this author
First published: 04 July 2023
Citations: 2

Graphical Abstract

The hydrogen atoms of a covalent organic framework on the framework and guest molecules were located using cryo-3D electron diffraction for the first time. The host–guest interactions in the framework material were clarified by locating the hydrogen atoms.

Abstract

Covalent organic frameworks (COFs) have wide-ranging applications, and their host–guest interactions play an essential role in the achievement of COF functions. To investigate these host–guest interactions, it is necessary to locate all atoms, especially hydrogen atoms. However, it is difficult to determine the hydrogen atomic positions in COFs because of the complexities in synthesizing high-quality large single crystals. Three-dimensional electron diffraction (3D ED) has unique advantages for the structural determination of nanocrystals and identification of light atoms. In this study, it was demonstrated for the first time that the hydrogen atoms of a COF, not only on the framework but also on the guest molecule, can be located by 3D ED using continuous precession electron diffraction tomography (cPEDT) under cryogenic conditions. The host–guest interactions were clarified with the location of the hydrogen atoms. These findings provide novel insights into the investigation of COFs.

Conflict of interest

The authors declare no conflict of interest.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.