Sorption isotherms of methane in Zn(2)(bdc)(2)(dabco) are measured up to a pressure of 35 bar in the temperature range between 198-296 K. The methane sorption measurements at 296 K showed an uptake of 137 cm(3) cm(-3) at 35 bar. The enthalpy of methane adsorption for Zn(2)(bdc)(2)(dabco) estimated by the virial equation is 13.6 kJ mol(-1) at zero coverage. X-ray structure analysis of methane-adsorbed Zn(2)(bdc)(2)(dabco) by synchrotron radiation at 90 K revealed that methane molecules occupy three independent sorption sites (A, B, and C) with a stoichiometry of Zn(2)(bdc)(2)(dabco) x 6.69 CH(4), which is consistent with the results of the gas sorption measurements at 198 K. In a cavity, eight symmetry-related methane sorption sites A are located near the {Zn(2)(CO(2))(4)} paddle-wheel units, while four symmetry-related methane sorption sites B are near the center of the small windows along the a and b axes. Both A and B sites are half-occupied. Methane molecules occupying sites A are not only in van der Waals contact with the paddle-wheel units, but also interact with the phenyl rings of bdc ligands through partial pi-HC interactions. Methane molecules in B sites interact with the side of the phenyl rings through van der Waals interaction. The site C, located at the center of the cavity, is a secondary sorption site; methane molecules occupying sites C are in van der Waals contact with those in sites A and B.

A series of chromium­(III) terephthalates MIL-101 with different anion composition of the porous matrix have been synthesized and characterized in adsorption reactions with nitrogen, hydrogen, and methane by volumetric and calorimetric measurements at pressures up to 3.2 MPa. A peculiar local maximum of H2 adsorption heat at concentrations of 0.7–0.9 mmol/g corresponding to the filling of nanosized supertetrahedra was found. It has been shown that the substitution of the fluorine anions by Cl– strongly affected accessibility of these micropores toward gas molecules.

Ultra-high-pressure hydrogen-storage performance (up to 1900 bar) was investigated for mesoporous chromium terephthalate MIL-101 and its inclusion compounds containing ionic clusters [Re(4)S(4)F(12)](4-) and [SiW(11)O(39)](7-) within the porous framework. The maximum specific hydrogen uptake values (total) for MIL-101 are 12.3 (at 81) and 7.2 wt. % (at 293 K). Such unique measurement conditions allowed us to identify the density of the absorbed hydrogen directly from the excess sorption isotherm curves. The corresponding density values were found to be almost comparable at low temperature, but significantly different at ambient temperature, which indicated an increase of more than double in the number of hydrogen binding sites in the case of the inclusion compounds with rhenium clusters.

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The single-phase multi-principal-component CoFeMnTiVZr alloy was obtained by rapid solidification and examined by a combination of electrochemical methods and gas–solid reactions.