Rich Polymorphism of a Metal-Organic Framework in Pressure-Temperature Space.
Authors
Chibani, Siwar
Wilson, Craig W
Kleppe, Annette K
Publication Date
2019-06Journal Title
Journal of the American Chemical Society
ISSN
0002-7863
Publisher
American Chemical Society
Volume
141
Issue
23
Pages
9330-9337
Language
eng
Type
Article
This Version
AM
Physical Medium
Print-Electronic
Metadata
Show full item recordCitation
Widmer, R., Lampronti, G. I., Chibani, S., Wilson, C. W., Anzellini, S., Farsang, S., Kleppe, A. K., et al. (2019). Rich Polymorphism of a Metal-Organic Framework in Pressure-Temperature Space.. Journal of the American Chemical Society, 141 (23), 9330-9337. https://doi.org/10.1021/jacs.9b03234
Abstract
We present an in-situ powder X-ray diffraction study on the phase stability and polymorphism of the metal-organic framework ZIF-4, Zn(Imidazolate)2, at simultaneous high-pressure and high- temperature, up to 8 GPa and 600 °C. The resulting pressure-temperature phase diagram reveals four, previously unknown, high-pressure-temperature ZIF phases. The crystal structures of two new phases – ZIF-4-cp-II and ZIF-hPT-II – were solved by powder diffraction methods. The total energy of ZIF-4-cp-II was evaluated using density functional theory calculations and was found to lie in between that of ZIF-4 and the most thermodynamically stable polymorph, ZIF-zni. ZIF-hPT-II was found to possess a doubly-interpenetrated diamondoid-topology and is isostructural with previously reported Cd(Imidazolate) and Hg(Imidazolate) phases. This phase
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exhibited extreme resistance to both temperature and pressure. The other two new phases could
be assigned with a unit cell and space group, though their structures remain unknown. The pressure-temperature phase diagram of ZIF-4 is strikingly complicated when compared with that of the previously investigated, closely related ZIF-62, and demonstrates the ability to traverse complex energy landscapes of metal-organic systems using the combined application of pressure and temperature.
Sponsorship
Royal Society (UF150021)
Identifiers
External DOI: https://doi.org/10.1021/jacs.9b03234
This record's URL: https://www.repository.cam.ac.uk/handle/1810/293050
Rights
All rights reserved