A combination of topological rules and quantum chemical calculations has facilitated the development of a rational metal-organic framework (MOF) synthetic strategy using the tritopic benzene-1,3,5-tribenzoate (btb) linker and a neutral cross-linker 4,4'-bipyridine (bipy). A series of new compounds, namely [M(2)(bipy)](3)(btb)(4) (DUT-23(M), M = Zn, Co, Cu, Ni), [Cu(2)(bisqui)(0.5)](3)(btb)(4) (DUT-24, bisqui = diethyl (R,S)-4,4'-biquinoline-3,3'-dicarboxylate), [Cu(2)(py)(1.5)(H(2)O)(0.5)](3)(btb)(4) (DUT-33, py = pyridine), and [Cu(2)(H(2)O)(2)](3)(btb)(4) (DUT-34), with high specific surface areas and pore volumes (up to 2.03 m(3)  g(-1) for DUT-23(Co)) were synthesized. For DUT-23(Co), excess storage capacities were determined for methane (268 mg g(-1) at 100 bar and 298 K), hydrogen (74 mg g(-1) at 40 bar and 77 K), and n-butane (99 mg g(-1) at 293 K). DUT-34 is a non-cross-linked version of DUT-23 (non-interpenetrated pendant to MOF-14) that possesses open metal sites and can therefore be used as a catalyst. The accessibility of the pores in DUT-34 to potential substrate molecules was proven by liquid phase adsorption. By exchanging the N,N donor 4,4'-bipyridine with a substituted racemic biquinoline, DUT-24 was obtained. This opens a route to the synthesis of a chiral compound, which could be interesting for enantioselective separation.

Molecular hydrogen storage in metal–organic frameworks (MOFs) is one possibility for on‐board storage in fuel‐cell vehicles, but so far generally only the gravimetric hydrogen storage capacity has been considered. Here we analyze the volumetric absolute hydrogen uptake of many MOFs measured at 77 K and 2.0–2.5 MPa in our laboratory in recent years and correlate these to their structure. A linear relation is found for the volumetric absolute hydrogen uptake as a function of the volumetric surface area, which yields the same hydrogen surface density as in Chahine's rule. Furthermore, the experimental data show a correlation between the specific volume and the specific surface area, which is used to develop a phenomenological model for the volumetric absolute uptake as a function of the gravimetric absolute uptake. Most of the MOFs follow this relation. However, the interpenetrated framework, CFA‐7, shows the strongest deviation and the highest volumetric absolute hydrogen storage capacity at 77 K and 2.0 MPa.

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A large number of different porous materials has been investigated for their hydrogen uptake over a wide pressure range and at different temperature. From the absolute adsorption isotherms, the enthalpy of adsorption is evaluated for a wide range of surface coverage. The usable capacity, defined as the amount of hydrogen released between a maximum tank pressure and a minimum back pressure for a fuel cell, is analyzed for isothermal operation. The usable capacity as a function of temperature shows a maximum which defines the optimum operating temperature. This optimum operating temperature is higher for materials possessing a higher enthalpy of adsorption. However, the fraction of the hydrogen stored overall that can be released at the optimum operating temperature is higher for materials with a lower enthalpy of adsorption than for the ones with higher enthalpy.

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