Herein, we report that a new flexible coordination network, NiL₂ (L=4‐(4‐pyridyl)‐biphenyl‐4‐carboxylic acid), with diamondoid topology switches between non‐porous (closed) and several porous (open) phases at specific CO₂ and CH₄ pressures. These phases are manifested by multi‐step low‐pressure isotherms for CO₂ or a single‐step high‐pressure isotherm for CH₄. The potential methane working capacity of NiL₂ approaches that of compressed natural gas but at much lower pressures. The guest‐induced phase transitions of NiL₂ were studied by single‐crystal XRD, in situ variable pressure powder XRD, synchrotron powder XRD, pressure‐gradient differential scanning calorimetry (P‐DSC), and molecular modeling. The detailed structural information provides insight into the extreme flexibility of NiL₂. Specifically, the extended linker ligand, L, undergoes ligand contortion and interactions between interpenetrated networks or sorbate–sorbent interactions enable the observed switching.

中文翻译：

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互穿的类金刚石配位网络的高多孔相和无孔相之间的可逆切换，在甲烷存储压力下展现出开门的作用

在此，我们报告了一种新的柔性配位网络NiL ₂（L = 4-（4-吡啶基）-联苯-4-羧酸），在非多孔（封闭）相和多个多孔（开放）相之间具有类金刚石拓扑切换在特定的CO ₂和CH ₄压力下。这些阶段表现为CO ₂的多步低压等温线或CH ₄的单步高压等温线。NiL ₂的潜在甲烷工作能力接近压缩天然气，但压力要低得多。客体诱导的NiL ₂相变通过单晶XRD，原位变压粉末XRD，同步加速器粉末XRD，压力梯度差示扫描量热法（P‐DSC）和分子模型进行了研究。详细的结构信息可帮助您深入了解NiL ₂的极高灵活性。具体而言，扩展的连接子配体L经历配体扭曲，并且互穿网络之间的相互作用或山梨酸酯与吸附剂的相互作用使观察到的转换成为可能。