We offer insights into how network topology influences stability of metal-organic frameworks and suggest the application of rare sheet-MOFs, where metal ions and linkers form infinite 2D units (SBUs) as a strategy for achieving higher stability. We also demonstrate a unified topology approach to MOFs exemplified by the dot-, rod-, and sheet-MOFs reported. These MOFs are based on vicinal dicarboxylates, which we propose as a way to prepare rod-MOFs. Cyclic voltammetry suggests Ce(IV)-MOFs as being more stable than expected with potential electrochemical applications.

Nine metal–organic frameworks have been prepared with the hexagon-shaped linker 1,2,3,4,5,6-hexakis­(4-carboxyphenyl)­benzene (H6cpb) by solvothermal reactions in dimethylformamide (dmf) or dimethylacetamide (dmac) with acetic acid or formic acid as modulators: [Bi2(cpb)­(acetato)2(dmf)2]·2dmf CTH-6 forms a rtl-net; 2­(H2NMe2)­[Cu2(cpb)] CTH-7 forms a kgd-net; [Fe4(cpb)­(acetato)2(dmf)4] CTH-8 and [Co4(cpb)­(acetato)2(dmf)4] CTH-9 are isostructural and form yav-nets; 2­(HNEt3)­[Fe2(cpb)] CTH-10 and the two polymorphs of 2­(H2NMe2)­[Zn2(cpb)]·1.5dmac, Zn-MOF-888 and CTH-11, show kgd-nets; [Cu2(cpb)­(acetato)2(dmf)2]·2dmf, CTH-12, forms a mixed coordination and hydrogen-bonded sql-net; and 2­(H2NMe2)­[Zn2(cpb)] CTH-13, a similarly mixed yav-net. Surface area values (Brunauer–Emmett–Teller, BET) range from 34 m2 g–1 for CTH-12 to 303 m2 g–1 for CTH-9 for samples activated at 120 °C in dynamic vacuum. All compounds show normal (10-fold higher) molar CO2 versus N2 uptake at 298 K, except the 19-fold CO2 uptake for CTH-12 containing Cu­(II) dinuclear paddle-wheels. We also show how perfect hexagons and triangles can combine to a new 3D topology laf, a model of which gave us the idea of foldable network topologies, as the laf-net can fold into a 2D form while retaining the local geometry around each vertex. Other foldable nets identified are cds, cds-a, ths, sqc163, clh, jem, and tfc covering the basic polygons and their combinations. The impact of this concept on “breathing” MOFs is discussed. I2 sorption, both from gas phase and from MeOH solution, into CTH-7 were studied by time of flight secondary ion mass spectrometry (ToF-SIMS) on dried crystals. I2 was shown to have penetrated the crystals, as layers were consecutively peeled off by the ion beam. We suggest ToF-SIMS to be a method for studying sorption depth profiles of MOFs.

The host compounds tetrakis(4-bromophenyl) ethylene and its iodo-analogue form inclusion compounds with a series of chloro-and iodo-methanes. Their structures have been elucidated, and their nonbonded halogen···halogen contacts have been analyzed and classified. Their kinetics of desolvation have been studied, and the concomitant activation energies have been established. Five of the clathrates are isostructural and display similar activation energies of desolvation, thus correlating structure and function. The velocity of the enclathration for the solid host−methyl iodide vapor reactions and associated rate law have been established.

A series of co-crystals of vanillic acid (VA) with caffeine (CAF), theophylline (THP), theobromine (THB), nicotinamide (NAM), isonicotinamide (INM), acridine (ACR) and urea (U) have successfully been prepared. The co-crystals involving the methylated xanthines indicate different host: guest ratios with co-crystals VA·2CAF, 2VA·THP and the co-crystal hydrate VA·THB·2H 2 O. The nicotinamide and acridine co-crystals (VA·NAM and VA·ACR) displayed 1 : 1 molar ratios in contrast to the isonicotinamide co-crystal hydrate 2VA·2INM·2H 2 O. Co-crystallisation of vanillic acid with urea gave 2VA·2U. The co-crystals and co-crystal hydrates were characterised by single crystal X-ray diffraction and thermal analysis. Grinding and slurry experiments were also performed.

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