AbstractA 2D‐to‐2D (2D: two‐dimensional) structural transformation accompanying significant bond rearrangement and coordination environment change is demonstrated in a coordination polymer (CP) comprised of copper(II) ions and terephthalate (BDC2−) ligands for the first time. When immersed in water, a free‐standing membrane of 2D Cu(BDC)(DMF) (Cu‐1; DMF: N,N‐dimethylformamide) transforms into 2D Cu(BDC)(H2O)2 (Cu‐2) while maintaining its highly oriented layered structure. In the 2D sheet, paddlewheel‐type CuII dimers coordinated with four bidentate BDC ligands in a square‐planar array in Cu‐1 were released to form uniform aqua‐bridged CuII chains, which are cross‐linked with each other by unidentate BDC ligands, in Cu‐2. The present facile approach to implement the 2D‐to‐2D transformation accompanied by bond rearrangement, which is characteristic of CPs, leads to a marked increase in in‐plane magnetic susceptibility and proton conductivity. In situ experiments in support of theoretical calculations unveiled the energy diagram that governs the unique structural transformation.
摘要 首次在由铜(II)离子和对苯二甲酸盐(BDC2-)配体组成的配位聚合物(CP)中展示了伴随着显著的键重排和配位环境变化的二维到二维(2D:二维)的结构转变。当浸入水中时,独立的二维 Cu(BDC)(DMF)膜(Cu-1;DMF:N,N-二甲基甲酰胺)会转变为二维 Cu(BDC)(H2O)2(Cu-2),同时保持其高度取向的层状结构。在二维薄片中,Cu-1 中与四个双叉 BDC 配体配位的桨轮型 CuII 二聚体呈方阵排列,它们被释放出来,形成均匀的水桥 CuII 链,这些链在 Cu-2 中通过非双叉 BDC 配体相互交联。这种简单的方法实现了二维到二维的转变,并伴随着氯化石蜡特有的键重排,从而显著提高了面内磁感应强度和质子电导率。支持理论计算的现场实验揭示了支配这种独特结构转变的能量图。