顺-/反-烯烃异构体在石油化工行业具有重要应用价值，然而其极为相似的物理化学性质为节能高效的分离纯化技术的开发带来了巨大的挑战。本文设计的阴离子柱撑超微孔金属-有机框架材料，即ZU-36-Ni和ZU-36-Fe，首次实现了基于分子筛分效应的顺-/反-2-丁烯高效分离。ZU-36-Ni 具有智能的客体适应型孔道结构，其对反-2-丁烯呈现出高吸附容量（2.45 mmol∙g⁻¹）并对顺-2-丁烯高效排阻，可从混合气中分离获得99.99%的高纯度顺-2-丁烯气体。密度泛函理论计算表明：当反-2-丁烯进入孔道时，ZU-36-Ni 的有机配体在主-客体相互作用下可定向旋转，从而导致孔穴扩张并使孔道更加适应反-2-丁烯形状及尺寸，加之ZU-36-Ni 具有可匹配反-2-丁烯三维尺寸的最优孔穴维度，使得反-2-丁烯可以被高效吸附。ZU-36-Ni的适应性行为可最大限度地强化ZU-36-Ni 和反-2-丁烯的主-客体作用，不仅有利于提升反-2-丁烯的优先吸附及动力学扩散行为，同时可实现对顺-2-丁烯的高效分子筛分。本工作为拓展孔穴工程在先进智能或适应型多孔材料在客体分子辨识领域的应用提供了新思路。

Trans-/cis-olefin isomers play a vital role in the petrochemical industry. The paucity of energy-efficient technologies for their splitting is mainly due to the similarities of their physicochemical properties. Herein, two new tailor-made anion-pillared ultramicroporous metal–organic frameworks (MOFs), ZU-36-Ni and ZU-36-Fe (GeFSIX-3-Ni and GeFSIX-3-Fe) are reported for the first time for the efficient trans-/cis-2-butene (trans-/cis-C4H8) mixture splitting by enhanced molecular exclusion. Notably, ZU-36-Ni unexpectedly exhibited smart guest-adaptive pore channels for trapping trans-C4H8 with a remarkable adsorption capacity (2.45 mmol∙g−1) while effectively rejecting cis-C4H8 with a high purity of 99.99%. The dispersion-corrected density functional theory (DFT-D) calculation suggested that the guest-adaptive behavior of ZU-36-Ni in response to trans-C4H8 is derived from the organic linker rotation and the optimal pore dimensions, which not only improve the favorable adsorption/diffusion of trans-C4H8 with optimal host–guest interactions, but also enhance the size-exclusion of cis-C4H8. This work opens a new avenue for pore engineering in advanced smart or adaptive porous materials for specific applications involving guest molecular recognition.