STRUCTURAL AND SPECTRAL PROPERTIES OF 3-SUBSTITUTEDPHENYL-1,5-DIPHENYLFORMAZANS: A QUANTUM CHEMICAL STUDY
H. Tezcan1, N. Tokay2
1Gazi University, Ankara, Turkey
habibe@gazi.edu.tr
2Hacettepe University, Ankara, Turkey
Ключевые слова: formazans, substituent effects, UV-vis spectra, TD-DFT, PCM
Страницы: 269-277
Аннотация
The structural and optical properties of 3-substitutedphenyl-1,5-diphenylformazans are studied by quantum chemical methods. The density functional theory (DFT) is employed to optimize the ground state geometries of formazans substituted with different electron donating and withdrawing groups in both gas and solvent phases. The absorption spectra of formazan derivatives are calculated using time dependent density functional theory (TD-DFT). The polarizable continuum model (PCM) calculations of 3-substitutedphenyl-1,5-diphenylformazans are performed for bulk solvent effects. The geometrical parameters, vibrational frequencies, and relative stabilities of isomers of 3-substitutedphenyl-1,5-diphenylformazans are studied. The results obtained by TD-DFT calculations reveal that the substitution of electron withdrawing and donating substituents affects the absorption spectra of 3-substitutedphenyl-1,5-diphenylformazans. The calculated maximum absorption wavelengths (λmax) are highly consistent with the experimental values as found from UV-vis spectra.
DOI: 10.15372/JSC20170205 |
