The formation of biimidazoldiium structures by the introduction of methyl substituents on the N atoms at the 3 and 3′ positions of 2,2′-biimidazoles led to increments in the Stokes shift of these structures. Based on time-dependent density functional theory (TDDFT) calculations, the imidazolium rings become distorted and the N atoms of the imidazolium rings underwent structural changes through sp² to sp³ rehybridization in the excited states.

中文翻译：

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通过形成2,2'-双咪唑鎓盐增加斯托克斯位移

通过在2,2'-联咪唑的3和3'位置的N原子上引入甲基取代基，形成双咪唑结构，导致这些结构的斯托克斯位移增加。根据时间相关的密度泛函理论（TDDFT）计算，咪唑环变得扭曲，并且咪唑环的N原子在激发态下通过sp ²至sp ^3的再杂化而发生结构变化。