Aggregation induced emissive carbazole-based push pull NLOphores: Synthesis, photophysical properties and DFT studies. (January 2016)

• Record Type: Journal Article
• Authors: Lanke, Sandip K.; Sekar, Nagaiyan
• Is Part Of: Dyes and pigments. Volume 124(2016)
• Page Start: 82
• Page End: 92
• Publication Date: 2016-01
• Subjects: Aggregation induced emission -- Photophysical properties -- Twisted intramolecular charge transfer (TICT) -- Solvatochromism -- Polarizability -- Density functional theory (DFT); Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2015.09.013
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: 2-Alkoxy-9-methyl-9 H -carbazole-3-carbaldehyde based push pull chromophore were efficiently synthesized by a multi-step reaction starting from 9 H -carbazole-2-ol. The fluorescence properties of these D–π–A chromophores were investigated in various solvents of varying polarities and in mixed solvent solutions of DMF and H2 O. They exhibited low fluorescent intensity in solution but a high fluorescent intensity in aggregate forms and in their solid state due to the promising aggregation-induced emission enhancement characteristics. These dyes were fully characterized by FT-IR, 1 H NMR and HRMS spectra. The ratio of ground to excited state dipole moment of the novel push pull chromophore were calculated by Bakhshiev and Bilot–Kawski correlations. All the four dyes show more or less twisted intramolecular charge transfer (TICT) characteristics. They show a large first hyperpolarizability value ranging from 189–721 × 10 −30 esu by theoretical method and 73–330 × 10 −30 esu by experimental method. Graphical abstract: Highlights: Novel carbazole based push–pull dyes were synthesized. Dyes exhibited aggregation-enhanced emission and solvatochromism. Dipole moment determination using solvatochromism and DFT method. Nonlinear optical property study based on solvatochromism and DFT. DFT and TDDFT computation were performed for photophysical property study.