Syntheses, crystal structure, luminescent behaviors and Hirshfeld surface of salts with imidazole and benzimidazole-yl scaffolds

•Two salts with imidazole and benzimidazole-yl skeletons have been obtained.•Their crystal state structures were structurally characterized by single crystal X-ray diffraction.•The enormous red-shifted luminescent peaks can be modulated by the substituted groups.•The emission maxima are proportional to the C∙∙∙C intermolecular contacts.