Linker extensions in metal–organic frameworks: a way to isoreticular networks or new topologies?

Abstract

The synthesis of a new microporous metal–organic framework (UHM-7) under solvothermal conditions and its characterisation by single-crystal X-ray analysis and several physisorption measurements is presented. The MOF structure is composed of copper ions and a novel non-linear silicon containing tetracarboxylate linker and exhibits an unprecedented topology (chs-1). The surface area and the micropore volume were determined by nitrogen physisorption measurements to be 1290 m² g⁻¹ and 0.48 cm³ g⁻¹, respectively. Furthermore, UHM-7 shows gas storage capacities of 1.5 wt% H₂ at 77 K, 0.5 mmol g⁻¹ CH₄ at 298 K and 2.3 mmol g⁻¹ CO₂ at 298 K.