Decoupled MOF breathing : pressure-induced reversal of correlation between orthogonal motions in a diamondoid framework

Tools

Brammer, Lee and Ashworth, David and Carrington, Elliot J. and Roseveare, Thomas M. and McMonagle, Charles J. and Ward, Martin R. and Fletcher, Ashleigh J. and Düren, Tina and Warren, Mark R. and Moggach, Stephen A. and Oswald, Iain D.H. (2025) Decoupled MOF breathing : pressure-induced reversal of correlation between orthogonal motions in a diamondoid framework. Angewandte Chemie International Edition. e202504297. ISSN 1521-3773 (In Press) (https://doi.org/10.1002/anie.202504297)

[thumbnail of Ashworth-etal-ACIE-2025-Decoupled-MOF-breathing] Text. Filename: Ashworth-etal-ACIE-2025-Decoupled-MOF-breathing.pdf
Accepted Author Manuscript
Restricted to Repository staff only until 1 January 2099.
License: Creative Commons Attribution 4.0 logo
Download (699kB) | Request a copy

Abstract

Responsive porous materials can outperform more rigid analogues in applications requiring precise triggering of molecular uptake/release, switching or gradual change in properties. We have uncovered an unprecedented dynamic response in the diamondoid MOF SHF-62 , (Me2NH2)[In(BDC-NHC(O)Me)2] (BDC=1,4-benzenedicarboxylate), by using pressure as a stimulus. SHF-62 exhibits two distinct framework “breathing” motions involving changes in (1) cross-section and (2) length of its 1D pores. Our study using synchrotron single-crystal X-ray diffraction in sapphire-capillary (p < 0.15 GPa) and diamond-anvil (0.15 < p < 5 GPa) cells reveals that different pressure regimes trigger positive and negative correlation between these two motions, requiring an unprecedented mechanical decoupling. Specifically, the DMF-solvated framework SHF-62-DMF , in DMF as pressure-transmitting medium, undergoes initial hyperexpansion of pore cross-section (p ≤ 0.9 GPa), due to DMF ingress, followed by reversal/reduction at p > 0.9 GPa while pore length contracts for all pressure increases, revealing decoupling of the two framework deformations. By contrast, non-penetrating medium FC-70 imposes correlated compression (p < 1.4 GPa) of pore cross-section and length, resembling framework activation/desolvation motions but of greater magnitude. Similar behaviour occurs for SHF-62-CHCl3 in CHCl3 (p < 0.14 GPa), suggesting minimal ingress of CHCl3. These findings change our understanding of MOF dynamic responses and provide a platform for future responsive materials development.

ORCID iDs

Brammer, Lee, Ashworth, David ORCID logoORCID: https://orcid.org/0000-0002-7897-2702, Carrington, Elliot J., Roseveare, Thomas M., McMonagle, Charles J., Ward, Martin R. ORCID logoORCID: https://orcid.org/0000-0003-0013-5004, Fletcher, Ashleigh J. ORCID logoORCID: https://orcid.org/0000-0003-3915-8887, Düren, Tina, Warren, Mark R., Moggach, Stephen A. and Oswald, Iain D.H. ORCID logoORCID: https://orcid.org/0000-0003-4339-9392;
CORE (COnnecting REpositories)