Figure shows ESF maps that summarize the propensity of TPhP, TPyP, and TBAP to crystallize to form extended π-π stacks with significant overlap between the pyrene cores. In this analysis, we define an extended π-π stack as four or more nearly co-parallel molecules with limits on the separation between centres of mass (see SI, section 1.4 for details). Due to the translational symmetry, this is equivalent to infinite stacks in almost all cases. All three of these molecules have similar energetic distributions of stacked versus unstacked structures. Note that many unstacked structures are hidden in Figure (see SI, Figure ). In all three cases, the low-energy edge of the energy-density distribution is dominated by structures containing πstacked columns. One key difference is the presence of low-energy spikes on the TBAP landscape, discussed above, which are not present for TPhP or TPyP. The structures within these deep basins on the lattice energy surface all show extended π-π stacking; that is, these regions of enhanced stability are explicitly linked to π-π stacking. We would therefore predict a priori that TBAP is a more promising candidate for -stacked HOFs than either of its two structural analogues, TPhP or TPyP.