A new supramolecular cocrystal of bis(3-hydroxy-1-methylpyridin-1-ium iodide)-18-crown-6 (I) has been synthesized successfully from 3-hydroxypyridine, methyl iodide and 18-crown-6 (18C6). The cocrystal was characterized by FT-IR, UV-DRS and PL spectroscopy, single crystal and powder X-ray diffraction (XRD) analysis, SEM and EDS analysis, and thermogravimetric analysis. The bulk phase purity of the compound is confirmed by powder XRD analysis, whereas single-crystal XRD confirms that it packs in a monoclinic system with centrosymmetric space group (P21/c). Single crystal XRD shows that the asymmetric unit is C6H12O3, [C6H8NO]+[I]¯. The presence of C–H⋯O, C–H⋯I and O–H⋯I intermolecular contacts helps to achieve crystal cohesion. The direct band gap energy has been estimated to be 3.21 eV using diffuse reflectance spectral measurements. Thermogravimetric analysis was employed to determine the compound’s thermal behaviour concerning temperature. EDS and SEM investigations were used to examine the elemental composition and surface morphology of the compound.

中文翻译：

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双(3-羟基-1-甲基吡啶-1-碘化鎓)-18-crown-6超分子共晶的合成及结构表征

以3-羟基吡啶、碘甲烷和18-crown-6 (18C6)为原料，成功合成了双(3-羟基-1-甲基吡啶-1-碘化鎓)-18-crown-6 (I)的新型超分子共晶。通过 FT-IR、UV-DRS 和 PL 光谱、单晶和粉末 X 射线衍射 (XRD) 分析、SEM 和 EDS 分析以及热重分析对共晶进行了表征。该化合物的体相纯度通过粉末 XRD 分析得到证实，而单晶 XRD 证实它堆积在具有中心对称空间群的单斜晶系中（磷21/C）。单晶XRD显示不对称单元为C6H12氧3， [C6H8不]+[我。 C-H⋯O、C-H⋯I 和 O-H⋯I 分子间接触的存在有助于实现晶体内聚力。使用漫反射光谱测量估计直接带隙能量为 3.21 eV。采用热重分析来确定化合物与温度有关的热行为。 EDS 和 SEM 研究用于检查化合物的元素组成和表面形态。