Design and structures of porous MOF crystals largely composed of nothing

A strategy based on reticulating metal ions and organic carboxylate links into extended networks has been advanced to a point that allowed the design of porous structures in which pore size and functionality could be varied systematically.The pore size can be varied from 3.5 to 28.8 Å and crystal density from 1 to 0.2 g/cm 3 .