To diversify metal-organic framework (MOF) structures beyond traditional Euclidean geometries and to create new charge-delocalization pathways beneficial for electrical conductivity, we constructed a novel double-helical MOF (dhMOF) by introducing a new butterfly-shaped electron-rich π-extended tetrathiafulvalene ligand equipped with four benzoate groups (ExTTFTB). The face-to-face oriented convex ExTTFTB ligands connected by Zn2(COO)4 paddlewheel nodes formed ovoid cavities suitable for guest encapsulation, while π-π-interaction between the ExTTFTB ligands of neighboring strands helped create new charge-delocalization pathways in iodine-mediated partially oxidized dhMOF. Iodine vapor diffusion led to oxidation of half of the ExTTFTB ligands in each double-helical strand to ExTTFTB•+ radical cations, which putatively formed intermolecular ExTTFTB/ExTTFTB•+ π-donor/acceptor charge-transfer chains with the neutral ExTTFTB ligands of an adjacent strand, creating supramolecular wire-like charge-delocalization pathways along the helix seams. In consequence, the electrical conductivity of dhMOF surged from 10-8 S/m up to 10-4 S/m range after iodine treatment. Thus, the introduction of the electron-rich ExTTFTB ligand with a distinctly convex π-surface not only afforded a novel double-helical MOF architecture featuring ovoid cavities and unique charge-delocalization pathways but also, more importantly, delivered a new tool and design strategy for future development of electrically conducting stimuli-responsive MOFs.

中文翻译：

---

具有蝴蝶形电子富集π扩展四硫富富瓦烯配体的导电双螺旋金属有机骨架的出现。

为了使传统的欧几里得几何形状以外的金属有机骨架（MOF）结构多样化，并创建有利于电导率的新的电荷离域路径，我们通过引入新的蝴蝶形富电子π-构造了新型双螺旋MOF（dhMOF）扩展的四硫富瓦烯配体，带有四个苯甲酸酯基团（ExTTFTB）。通过Zn2（COO）4桨轮节点连接的面对面定向凸ExTTFTB配体形成了适合客体封装的卵形腔，而相邻链的ExTTFTB配体之间的π-π相互作用有助于在碘-中形成新的电荷离域途径介导的部分氧化dhMOF。碘蒸气扩散导致每个双螺旋链中的一半ExTTFTB配体氧化为ExTTFTB•+自由基阳离子，它推定与相邻链的中性ExTTFTB配体形成分子间ExTTFTB / ExTTFTB•+π供体/受体电荷转移链，沿着螺旋接缝形成超分子线状电荷离域化路径。结果，在碘处理后，dhMOF的电导率从10-8 S / m上升到10-4 S / m。因此，引入具有明显凸形π表面的富电子的ExTTFTB配体不仅提供了新颖的双螺旋MOF结构，具有卵形腔和独特的电荷离域途径，而且更重要的是，提供了一种新的工具和设计策略用于导电刺激性MOF的未来发展。沿螺旋接缝形成超分子线状电荷离域通路。结果，在碘处理后，dhMOF的电导率从10-8 S / m上升到10-4 S / m。因此，引入具有明显凸形π表面的富电子的ExTTFTB配体不仅提供了新颖的双螺旋MOF结构，具有卵形腔和独特的电荷离域途径，而且更重要的是，提供了一种新的工具和设计策略用于导电刺激性MOF的未来发展。沿螺旋接缝形成超分子线状电荷离域通路。结果，在碘处理后，dhMOF的电导率从10-8 S / m上升到10-4 S / m。因此，引入具有明显凸形π表面的富电子的ExTTFTB配体不仅提供了新颖的双螺旋MOF结构，具有卵形腔和独特的电荷离域途径，而且更重要的是，提供了一种新的工具和设计策略用于导电刺激性MOF的未来发展。