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A multi‐stage core‐expansion method is proposed here as one component of the integrative binding‐site/extender/core‐expansion (BEC) strategy. The conceptual deconstruction of the partitioning ligand into three editable parts draws our focus onto progressive core expansion and allows the optimization of both acetylene uptake and selectivity. The effectiveness of this strategy is shown through a family of eight cationic pore‐partitioned materials containing three different partitioning ligands and various counter anions. The optimized structure, Co3‐cpt‐tph‐Cl (Hcpt=4‐(p‐carboxyphenyl)‐1,2,4‐triazole, H‐tph=(2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene) with the largest surface area and highest C2H2 uptake capacity (200 cm3/g at 298 K), also exhibits (desirably) the lowest CO2 uptake and hence the highest C2H2/CO2 selectivity. The successful boost in both C2H2 capacity and IAST selectivity allows Co3‐cpt‐tph‐Cl to rank among the best crystalline porous materials, ionic MOFs in particular, for C2H2 uptake and C2H2/CO2 experimental breakthrough separation. [ABSTRACT FROM AUTHOR]

We report here a strategy for making anionic pacs type porous materials by combining pore space partition with charge reallocation. The method uses the first negatively charged pore partition ligand (2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene, H‐tph) that simultaneously enables pore partition and charge reallocation. Over two dozen anionic pacs materials have been made to demonstrate their excellent chemical stability and a high degree of tunability. Notably, Ni3‐bdt‐tph (bdt=1,4‐benzeneditetrazolate) exhibits month‐long water stability, while CoV‐bdt‐tph sets a new benchmark for C2H2 storage capacity under ambient conditions for ionic MOFs. In addition to tunable in‐framework modules, we show feasibility to tune the type and concentration of extra‐framework counter cations and their influence on both stability and capability to separate industrial C3H8/C3H6 and C6H6/C6H12 mixtures. [ABSTRACT FROM AUTHOR]