Open Metal Sites within Isostructural Metal–Organic Frameworks for Differential Recognition of Acetylene and Extraordinarily High Acetylene Storage Capacity at Room Temperature

On the metal: Open metal sites within isostructural [M2(DHTP)] metal–organic frameworks (M=Co2+, Mn2+, Mg2+, and Zn2+; DHTP=2,5-dihydroxyterephthalate) exhibit differential molecular recognition with acetylene. The extremely strong interaction of Co2+ with acetylene (see structure) makes [Co2(DHTP)] the highest volumetric acetylene storage material with a capacity of 230 cm3 cm−3 at 295 K and 1 atm.