Herein, the control of the crystalline-state fluorescence of zwitterionic imidazolium 2-pyridin-3-olate 1 bearing linear alkyl chains via morphological variations is described, along with a mechanistic rationale. Crystals of 1a–e prepared from CH₃CN exhibited intense blue fluorescence under UV irradiation at 298 K, whereas crystals of 1e prepared from i-PrOH/Et₂O were less emissive under the same measurement conditions. Temperature-dependent emission spectra showed that emissive crystals of 1a–e experienced minimal emission decay with increasing temperature, whereas crystalline 1e, having a different polymorphism, was highly heat-quenchable. Single-crystal XRD established that less emissive, heat-quenchable crystal 1e had a lamellar structure supported by consecutive face-to-face arrangement with π-stacking interactions between imidazolium and pyridinolate moieties, whereas highly emissive, heat-resistant crystals 1d and 1e had a face-to-edge lamellar structure with CH-π interactions between the heteroaromatic rings.

在此，描述了通过形态变化控制带有线性烷基链的两性离子咪唑-2-吡啶-3-油酸酯1的结晶态荧光，以及机理原理。由CH ₃ CN制备的1a - e晶体在298 K的紫外线照射下表现出强烈的蓝色荧光，而由i -PrOH / Et ₂ O制备的1e晶体在相同的测量条件下发射率较低。温度相关的发射光谱表明，随着温度的升高，1a - e的发射晶体经历的发射衰减最小，而1e - e晶体具有不同的多态性，是高度可热淬灭的。单晶XRD证实发射率低，可热淬灭的晶体1e具有层状结构，该结构由连续的面对面排列以及咪唑鎓和吡啶鎓部分之间的π堆积相互作用支撑，而高发射率的耐热晶体1d和1e具有杂芳环之间具有CH-π相互作用的面对面层状结构。