To evaluate the impact of the flexible positional isomeric ligands thiophene-2-acetate (2tpacCOO) and thiophene-3-acetate (3tpacCOO) on the construction and self-assembly process of Pb(II) polymers, two novel compounds, [Pb(2tpacCOO)₂(H₂O)]_n (1) and [Pb(3tpacCOO)₂]_n (2), were prepared via a nonhydrothermal method with respect to green chemistry rules. The obtained polymers were fully characterized by elemental analysis, TG/DTG and PXRD, FT-IR, solid-state photoluminescence, DFT calculations and single-crystal X-ray diffraction. Each Pb(II) centre of 1 is 7-coordinated as a {PbO₇} chromophore while the Pb(II) centre of 2 is 6-coordinated as a {PbO₆} structure. The coordination polyhedron of 1 is best described as a distorted monocapped pentagonal pyramid, and 2 has a distorted trigonal prismatic shape. The crystallographic analysis and DFT calculations indicated the stereoactivity of the lone electron pair, which contributed to the hemidirected geometry of the Pb(II) environment. Due to the versatile binding modes of the ligands, complex 1 forms 1D stair-like chains with an SP 1-periodic net (4,4)(2,0) topology, and the underlying net of 2 is determined to have a 1D 2,4C4 topology. It is worth noting that the crystal structures of the obtained polymers are stabilized mainly by many hydrogen bonds as well as Pb⋯S and Pb⋯π tetrel interactions. Moreover, the PL data demonstrate the different influences of the isomers of linkers on photoluminescence properties. Polymer 1 might be a good candidate for obtaining solid-state photoluminescent materials.

中文翻译：

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探索噻吩-2-乙酸盐和噻吩-3-乙酸盐对Pb（II）聚合物的分子和超分子结构以及光致发光性能的结合方式

为了评估柔性位置异构体配体噻吩-2-乙酸盐（2tpacCOO）和噻吩-3-乙酸盐（3tpacCOO）对Pb（II）聚合物，两种新型化合物[Pb（2tpacCOO ）的构建和自组装过程的影响）₂（H ₂ O）] _n（1）和[Pb（3tpacCOO）₂ ] _n（2）是根据绿色化学规则通过非水热法制备的。通过元素分析，TG / DTG和PXRD，FT-IR，固态光致发光，DFT计算和单晶X射线衍射对所得聚合物进行了充分表征。每个Pb（II）中心为1作为{PbO ₇ }生色团，其为7配位，而{PbO ₆ }结构为2的Pb（II）中心。配位多面体1最好描述为扭曲的单峰五角锥，而2则具有扭曲的三棱柱形状。晶体学分析和DFT计算表明孤电子对的立体活性，这有助于Pb（II）环境的半定向几何结构。由于配体的通用结合模式，复合物1形成具有SP 1周期网（4,4）（2,0）拓扑结构和2的底层网的1D楼梯状链确定具有1D 2,4C4拓扑。值得注意的是，所得聚合物的晶体结构主要是通过许多氢键以及Pb⋯S和Pb⋯π锡et相互作用而稳定的。此外，PL数据表明接头的异构体对光致发光性质的不同影响。聚合物1可能是获得固态光致发光材料的良好候选者。