A unique 3D metal-organic framework based on a 12-connected pentanuclear Cd(II) cluster exhibiting proton conduction.

Solvothermal reaction of a TCA (TCA = 4,4',4''-tricarboxytriphenylamine) ligand with Cd(NO3)2 yielded a unique 3D 12-connected metal-organic framework of , which can be simplified as a (3,3,12)-connected 3-nodal net with a Schläfli symbol of {4(16)·6(36)·8(14)}{4(2)·6}2{4(3)}2 based on a 12-connected node of a pentanuclear Cd(ii) cluster and a three-connected organic linker of TCA. Compound exhibits both photoluminescence and proton conductivity. The luminescence properties of originate from the triphenylamine chromophore of the TCA ligand.