Syntheses, crystal structure, luminescent properties and Hirshfeld surface of a set of triazole-based salts

•Three triazole-based salts have been obtained.•Their crystal structures were solved by single crystal X–ray diffraction.•The luminescence behaviors can be modified by the organic anions.•The order of the emission peaks is consistent with that of C···C close contacts. To further investigate and explore the new luminescent materials, three new salts with triazole-based skeletons, namely, [HCNT]+X− (X = BS (1), PS (2) and SS∙H2O (3)) [CNT = 4-((1H-1,2,4-triazol-1-yl)methyl)benzonitrile, BS= benzene-sulfonic acid, PS = p-methyl phenyl sulfonic acid, SS = sulfosalicylic acid], have been prepared through the CNT and three sulfonic acids, respectively. Compounds 1-3 have been characterized by single–crystal X–ray diffraction, IR, UV-Vis, EA, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). In the target compounds, hydrogen bonds (N/O/C–H⋯O/N) and stacking interactions can be evidently observed, through which a three-dimensional framework will be built. The luminescent spectra of these compounds show that the maximal emission peaks in compounds 1-3 can be found to be 452, 441 and 472 nm, respectively. Compared with the free CNT, the emission maxima of compounds 1-3 are obviously red-shifted about 135, 124 and 155 nm, respectively. The Hirshfeld surface analysis further confirms that the C∙∙∙C close contacts can account for the photoluminescent spectra. [Display omitted]