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In pursuit of novel adsorbents with efficient adsorptive gas storage and separation capabilities remains highly desired and challenging. Although the documented zirconium‐tricarboxylate‐based metal–organic frameworks (MOFs) have displayed a variety of topologies encompassing underlying and geometry mismatch ones, the employed organic linkers are exclusively rigid and poorly presenting one type of conformation in the resultant structures. Herein, a used and semirigid tricarboxylate ligand of H3TATAB was judiciously selected to isolate a zirconium‐based spe‐MOF after the preliminary discovery of srl‐MOF. Single‐crystal X‐ray diffraction reveals that the fully deprotonated TATAB linker in spe‐MOF exhibits two distinct conformers, concomitant with popular Oh and rare S6 symmetrical Zr6 molecular building blocks, generating an unprecedented (3,3,12,12)‐c nondefault topology. Specifically, the spe‐MOF exhibits structurally higher complexity, hierarchical micropores, open metal sites free and rich electronegative groups on the pore surfaces, leading to relatively high methane storage capacity without considering the missing‐linker defects and efficient MTO product separation performance. [ABSTRACT FROM AUTHOR]

Amide‐functionalized metal–organic frameworks (AFMOFs) as a subclass of MOF materials have received great interest recently because of their intriguing structures and diverse potential applications. In this work, solvothermal reactions between indium nitrate and two mixed‐linkers afforded two new isoreticular 8‐connected trinuclear indium‐based AFMOFs of [(In3O)(OH)(L2)2(IN)2]⋅(solv)x (2‐In) and [(In3O)(OH)(L2)2(AIN)2]⋅(solv)x (NH2‐2‐In) (H2L2=4,4′‐(carbonylimino)dibenzoic acid and HIN=isonicotinic acid or HAIN=3‐aminoisonicotinic acid), respectively. Moreover, by means of reticular chemistry, an extended network of [(In3O)(OH)(L3)2(PB)2]⋅(solv)x(3‐In) (H2L3=4,4′‐(terephthaloylbis(azanediyl))dibenzoic acid, HPB=4‐(4‐pyridyl)benzoic acid) was also successfully realized after prolongation of the former dicarboxylate linker and HIN, resulting in a truly 8‐connected isoreticular AFMOF platform. These frameworks were structurally determined by single‐crystal X‐ray diffraction (SCXRD). Sorption studies further demonstrate that 2‐In and NH2‐2‐In exhibit not only high surface areas and pore volumes but also relatively high carbon capture capabilities (the CO2 uptakes reach 60.0 and 75.5 cm3 g−1 at 298 K and 760 torr, respectively) due to the presences of amide and/or amine functional groups. The selectivity of CO2/N2 and CO2/CH4 calculated by IAST are 10.18 and 12.43, 4.20 and 4.23 for 2‐In and NH2‐2‐In, respectively, which were additionally evaluated by mixed‐gases dynamic breakthrough experiments. In addition, high‐pressure gas sorption measurements show that both materials could take up moderate amounts of natural gas. [ABSTRACT FROM AUTHOR]

Using isoreticular chemistry allows the design and construction of a new rare-earth metal (RE) fcu-MOF with a suitable aperture size for practical steric adsorptive separations. The judicious choice of a relatively short organic building block, namely fumarate, to bridge the 12-connected RE hexanuclear clusters has afforded the contraction of the well-defined RE-fcu-MOF triangular window aperture, the sole access to the two interconnected octahedral and tetrahedral cages. The newly constructed RE (Y3+ and Tb3+) fcu-MOF analogues display unprecedented total exclusion of branched paraffins from normal paraffins. The resultant window aperture size of about 4.7 Å, regarded as a sorbate-size cut-off, enabled a complete sieving of branched paraffins from normal paraffins. The results are supported by collective single gas and mixed gas/vapor adsorption and calorimetric studies. [ABSTRACT FROM AUTHOR]

Using isoreticular chemistry allows the design and construction of a new rare-earth metal (RE) fcu-MOF with a suitable aperture size for practical steric adsorptive separations. The judicious choice of a relatively short organic building block, namely fumarate, to bridge the 12-connected RE hexanuclear clusters has afforded the contraction of the well-defined RE-fcu-MOF triangular window aperture, the sole access to the two interconnected octahedral and tetrahedral cages. The newly constructed RE (Y3+ and Tb3+) fcu-MOF analogues display unprecedented total exclusion of branched paraffins from normal paraffins. The resultant window aperture size of about 4.7 Å, regarded as a sorbate-size cut-off, enabled a complete sieving of branched paraffins from normal paraffins. The results are supported by collective single gas and mixed gas/vapor adsorption and calorimetric studies. [ABSTRACT FROM AUTHOR]

Tailored access for adsorbents is possible by using metal–organic frameworks (MOFs) with the appropriate pore‐aperture size. In their Communication on page 14353 ff., M. Eddaoudi and co‐workers construct a new rare earth metal (RE) fcu‐MOF with a triangular window aperture which provides unrivalled total exclusion of branched paraffins from normal paraffins. The optimal aperture size results from selecting the shortest linker from the available ditopic ligands. [ABSTRACT FROM AUTHOR]