Physisorption of molecular hydrogen based on neutral and negatively charged aromatic molecular systems has been evaluated using ab initio calculations to estimate the binding energy, DeltaH, and DeltaG at 298 ( approximately 77 bar) and 77 K (45 bar) in order to compare calculated results with experimental measurements of hydrogen adsorption. The molecular systems used in this study were corannulene (C(20)H(10)), dicyclopenta[def,jkl]triphenylene (C(20)H(10)), 5,8-dioxo-5,8-dihydroindeno[2,1-c]fluorene (C(20)H(10)O(2)), 6-hexyl-5,8-dioxo-5,8-dihydroindeno[2,1-c]fluorene (C(26)H(22)O(2)), coronene (C(24)H(12)), dilithium phthalocyanine (Li(2)Pc, C(32)H(16)Li(2)N(8)), tetrabutylammonium lithium phthalocyanine (TBA-LiPc, C(48)H(52)LiN(9)), and tetramethylammonium lithium phthalocyanine (TMA-LiPc, C(36)H(28)LiN(9)). It was found (a) that the calculated term that corrects 0 K electronic energies to give Gibbs energies (thermal correction to Gibbs energy, TCGE) serves as a good approximation of the adsorbent binding energy required in order for a physisorption process to be thermodynamically allowed and (b) that the binding energy for neutral aromatic molecules varies as a function of curvature (e.g., corannulene versus coronene) or if electron-withdrawing or -donating groups are part of the adsorbent. A negatively charged aromatic ring, the lithium phthalocyanine complex anion, [LiPc](-), introduces charge-induced dipole interactions into the adsorption process, resulting in a doubling of the binding energy of Li(2)Pc relative to corannulene. Experimental hydrogen adsorption results for Li(2)Pc, which are consistent with MD simulation results using chi-Li(2)Pc to simulate the adsorbent, suggest that only one side of the phthalocyanine ring is used in the adsorption process. The introduction of a tetrabutylammonium cation as a replacement for one lithium ion in Li(2)Pc has the effect of increasing the number of hydrogen molecules adsorbed from 10 (3.80 wt %) for Li(2)Pc to 24 (5.93 wt %) at 77 K and 45 bar, suggesting that both sides of the phthalocyanine ring are available for hydrogen adsorption. MD simulations of layered tetramethylammonium lithium phthalocyanine molecular systems illustrate that doubling the wt % H(2) adsorbed is possible via such a system. Ab initio calculations also suggest that layered or sandwich structures can result in significant reductions in the pressure required for hydrogen adsorption.

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A three-dimensional (3-D) multi-functional mixed valence Cu II /Cu I -MOF, {[Cu(CuI)2(2-pyzc)2H2O]2·H2O}n, (Hpyzc=pyrazine-2dicarboxylic acid), has been solvothermally synthesized and successfully characterized by FT-IR spectroscopy, elemental analysis, powder X-ray diffraction, thermal gravimetric analysis (TGA) and single-crystal X-ray diffraction. The structure posesses a 3-D open framework containing 1-D channels and shows tcj topological network with the Schläfli Symbol of (4 3 .6 12 ) (4 3 )2. This MOF exhibits selective adsorption of CO2/H2 over CH4/N2 and excellent catalytic activity in the oxidation of benzylic compounds and three-component coupling reactions of aromatic alkynes, tosylazide and diisopropylamine as a cooperative catalyst. The catalyst could be reused several times without significant degradation in catalytic activity.

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