We successfully designed the molecular assemblies with different symmetry patterns through minimal changes to their molecular components. However, it is desirable to predict the assembly patterns of the synthesized molecular structures in material design. Hence, we considered a possible guiding principle to govern the assembling pattern of the examined SubPc derivatives. Upon observing the correlation between the obtained crystals and their molecular assemblies, we noticed that the key element, governing the assembling patterns of SubPcs, can divide the obtained crystals into two major categories (orange and white cells in Table ). The crystals in orange cells are either polar crystals with a trigonal lattice or nonpolar crystals with the space group of P212121. In contrast, the crystals in white cells exhibit other structures. This distinction is not only based on the crystal symmetry but also our observation during the experiments to prepare single crystals. Specifically, the crystals in the orange cells could be prepared by adding a poor solvent, such as MeOH, to chloroform or chloronaphthalene solutions. Their crystallization conditions had to be optimized for each case (Table ). Considering these experimental differences, we investigated the characteristic differences between the molecules of the orange and white cells in their self-assembling patterns. We hypothesized that the molecular shape differentiates the assembling principle between the orange and white cells. Based on the obtained crystal data, the eight SubPcs used in this study were depicted with space-filling models (Figure ). Although the SubPc derivatives appear to have similar shapes at a glance, the shapes of SubPc derivatives in orange cells are close to a circle. In contrast, those in white cells deviate from a circular shape with increasing halogen size (Figure ). The dense packing of molecules during their assembly is thermodynamically preferable. Hence, 1D assemblies of SubPc derivatives prefer to assemble into close-packed structures whenever feasible. As the shape of SubPc derivatives gets close to circular ones, the cross-section of the corresponding 1D assemblies also becomes circular, forming close-packed structures.