Role of Solvent-Host Interactions That Lead to Very Large Swelling of Hybrid Frameworks
C. Serre,1*
C. Mellot-Draznieks,1,2
S. Surblé,1
N. Audebrand,3
Y. Filinchuk,4
G. Férey1
An unusually large expansion upon solvent adsorption occurs
without apparent bond breaking in the network of a series of
isoreticular chromium(III) or iron(III) diarboxylates labeled
MIL-88A to D [dicarbox = fumarate (88A); terephthalate (1,4-BDC)
(88B); 2,6-naphthalenedicarboxylate (2,6-NDC) (88C); and 4-4'-biphenyldicarboxylate
(4-4'-BPDC) (88D)]. This reversible "breathing" motion was analyzed
in terms of cell dimensions (extent of breathing), movements
within the framework (mechanism of transformation), and the
interactions between the guests and the skeleton. In situ techniques
show that these flexible solids are highly selective absorbents
and that this selectivity is strongly dependent on the nature
of the organic linker.
2 Royal Institution of Great Britain, 21 Albemarle Street, London W1S 4BS, UK.
3 Sciences Chimiques de Rennes (UMR-CNRS 6226), Université de Rennes 1, Avenue du Général Leclerc, 35042 Rennes Cedex, France.
4 Swiss Norwegian Beamlines (SNBL) at the European Synchrotron Radiation Facility (ESRF), rue Jules Horowitz, 38043 Grenoble, France.
* To whom correspondence should be addressed. E-mail: serre{at}chimie.uvsq.fr
