Vibrational modes and terahertz phenomena of the large-cage zeolitic imidazolate framework-71

Journal article

The zeolitic imidazole framework ZIF-71 has the potential to outperform other well-studied metal-organic frameworks due to its intrinsic hydrophobicity and relatively large pore size. However, a detailed description of its complex physical phenomena and structural dynamics has been lacking thus far. Herein, we report the complete assignment of the vibrational modes of ZIF-71 using high-resolution inelastic neutron scattering measurements and synchrotron radiation infrared spectroscopy, corroborated by density functional theory (DFT) calculations. With its 816 atoms per unit cell, ZIF-71 is the largest system yet for which frequency calculations have been accomplished employing the CRYSTAL17 DFT code. We discover low-energy terahertz dynamics such as gate-opening and shearing modes that are central to the functions and stability of the ZIF-71 framework structure. Nanoscale analytical methods based on atomic force microscopy (near-field infrared spectroscopy and AFM nanoindentation) further unravel the local chemical and mechanical properties of ZIF-71 single crystals.

Authors: Möslein, AF; Tan, J-C

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Chemical Society
• Journal: Journal of Physical Chemistry Letters
• Volume: 13
• Issue: 12
• Pages: 2838-2844
• Publication date: 2022-03-24
• Acceptance date: 2022-02-28
• DOI: 10.1021/acs.jpclett.2c00081
• EISSN: 1948-7185
• Pmid: 35324212
• Language: English
• Keywords: FFR