Dissecting the effects of water guest adsorption and framework breathing on the AlO4(OH)2 centres of metal–organic framework MIL-53 (Al) by solid state NMR and structural analysis†
Alexander E.
Khudozhitkov, 
a
Sergei S.
Arzumanov,
a
Anton A.
Gabrienko,
a
Daniil I.
Kolokolov
*a
and
Alexander G.
Stepanov
*a
a
Sergei S.
Arzumanov,
a
Anton A.
Gabrienko,
a
Daniil I.
Kolokolov
*a
and
Alexander G.
Stepanov
*a
Abstract
The relationship between the adsorption of water on MIL-53 (Al) MOF, the structural phase of MIL-53 (Al), and the quadrupole coupling constant of 27Al framework aluminium atom (QCC) of the MOF AlO4(OH)2 centres (Al-sites) has been investigated by combining solid-state 27Al MAS NMR spectroscopy with XRD analysis and DFT calculations. It is established that 27Al QCC is primarily sensitive to water adsorption to the Al-sites and by a minor extent to the framework contraction/expansion interconversions. We thus conclude that the 27Al MAS NMR method is sensitive enough to differentiate the effects of pore contractions and water adsorption to Al-sites basing on the changes of the QCC value.
Please wait while we load your content...
