Coordination of Pt2+ to a family of tunable Schiff base proligands directs the 12-component self-assembly of disk-shaped Pt4 rings in a head-to-tail fashion. Aggregation of these S4 sym. Pt4 macrocycles into columnar architectures was investigated by dynamic and static light scattering, NMR spectroscopy, powder X-ray diffraction, and transmission electron microscopy. Data from these expts. support the formation of columnar architectures for all of the structures studied except when bulky tris(4-tert-butylphenyl)methyl substituents were present. In this case, aggregation was limited to dimers in CHCl3 (Kdim = 3200 ± 200 L mol-1 at 25 °C) and a thermodn. anal. revealed that dimerization is an entropy driven process. Columnar architectures of Pt4 rings with branched 2-hexyldecyl substituents organize into lyotropic mesophases in nonpolar org. solvents. These new self-assembled supramols. are promising candidates to access nanotubes with multiple linear arrays of Pt2+ ions. [on SciFinder(R)]