Supermolecular Building Blocks (SBBs) and Crystal Design:  12-Connected Open Frameworks Based on a Molecular Cubohemioctahedron

The cubohemioctahedral supermolecular building blocks, SBBs, of formula M6(bdc)1212- (M = Ni, Co) (as illustrated) have the requisite symmetry to be cross-linked by rigid tetracarboxylato ligands in such a manner that 12-connected fcu nets with nanoscale features are generated. 3,5-H4ATC, L1, facilitates a structure with Ni that exhibits cavities with >2 nm maximum dimensions, whereas H4BIPA-TC, L2, forms a net with Co or Ni that exhibits cavities with >3 nm maximum dimensions.