Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1234771 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | 2013 | 12 Pages |
A new stilbazolium dye 4-{(E)-2-[4-(dimethylamino)naphthalen-1-yl]ethenyl}-1-methylquinolinium iodide monohydrate (DANSQI) having enlarged π-conjugated system was synthesized and characterized by X-ray diffraction, IR, Raman, UV–Vis, Fluorescence, 1H- and 13C NMR spectroscopy. Quantum chemical calculations were performed to obtain electronic structure and vibrational data, using DFT. The crystals are monoclinic, space group P21/n, with a = 8.0751(14), b = 25.839(4), c = 10.9031(15) Å, V = 2141.4(6) Å3, and Z = 4 (at 300(2) K). The unit cell contains four molecules of the dye, participating in weak intermolecular interactions. The cation is nearly flat with a deviation of the planarity of 5.08 (1)°. The dye investigated is the first stilbazolium iodide containing water molecule in the solid state therefore the N-dimethylamino group declines significantly from planarity, as indicated by C13N1C2C3 torsion angle of 16.08°. The dye studied shows solvatochromism of 84 nm in visible region and very large Stokes shift up to 253 nm. The intensity of fluorescence bands strongly depends on solvent polarity.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► New stilbazolium dye was synthesed. ► Single crystal X-ray analyses was performed and the structure was solved. ► The dye was investigated by IR, Raman, UV–Vis, Fluorescence, and NMR spectroscopy. ► We report the highest Stocks shift known up to now for stilbazolium dyes. ► We note a discrete structure of fluorescent spectra in polar solvents.