- Gazi University Journal of Science
- Vol: 30 Issue: 1
- MOLECULAR STRUCTURE ANALYSIS AND SPECTROSCOPIC PROPERTIES OF MONOAZO DISPERSE DYE FROM N,N-DIMETHYLA...
MOLECULAR STRUCTURE ANALYSIS AND SPECTROSCOPIC PROPERTIES OF MONOAZO DISPERSE DYE FROM N,N-DIMETHYLANILINE
Authors : Nurgul Seferoglu, Ömer Arslan, Ergin Yalçin, Müjgan Yaman, Zeynel Seferoglu
Pages : 175-189
View : 15 | Download : 4
Publication Date : 2017-03-14
Article Type : Other
Abstract :A monoazo disperse dye ( DMA ) has been prepared by diazotizing 4-aminoacetophenone and coupling with N , N -dimetylaniline. It was fully characterized using IR, 1 H-NMR, 13 C-NMR and mass spectral techniques. Structural assignments of the dye were made using X-ray crystallographic methods. The electronic absorption spectra of the dye in solvents of different polarities covers a λ max range of 437-460 nm. It is showed that the compound exhibits positive solvatochromism in solution, namely the absorption band is red shifted with increasing solvent polarity. In addition, the absorption properties of the dye change drastically upon acidification, as the protonation of β-nitrogen atom of the azo group increases the donor-acceptor interplay of the π system. The molecular structure, spectroscopic and nonlinear optical (NLO) properties of azo dye have been also investigated theoretically by performing Density Functional Theory (DFT) and Hartree–Fock (HF) levels of theory using the 6-31+G(d,p) basis set. The optimized geometries, electronic absorption spectra calculated using time-dependent DFT (TD-DFT) method and NMR spectra are evaluated via comparison with experimental values. In addition, thermal analysis shows that this dye is thermally stable up to 258 o C.Keywords : Monoazo disperse dye, UV-vis, DFT, Acidochromism, Non-linear optic (NLO).