Three new complexes [Cd(4-pmpmd)(1.5)(NO3)(2]) CHCl3 (1), [Cd(3-pmpmd)(1.5)(NO3)(2)]-EtOH (2), and [Zn(3-pmpmd)(1.5)(NO3)2]-MeOH (3) (3- or 4-pmpmd = NN'-bis(3- or 4-pyridylmethyl)pyromellitic diimide) containing T-shaped building blocks have been obtained from reactions between the long semirigid ligands 3- or 4-pmpmd and either cadmium or zinc nitrate. 1 forms noninterpenetrated 1 D molecular ladders that are linked via multiple, complementary intermolecular C-(HO)-O-... hydrogen bonds that effect the 3D alignment. 2 and 3 are isostructural and feature a noninterpenetrated 2D butterfly-shaped network with (6,3) topology. Multiple intermolecular C-(HO)-O-... hydrogen bonds exist between the 2D layers and generate the 3D framework. The structural differences between 1 and 2 or 3 are attributed to the different conformations adopted by the ligands, which illustrate the influence of positional isomerism on the resultant supramolecular architectures of metal complexes.