A computational study of the absorption spectra of 1‐substituted phenyl‐3,5‐diphenylformazans

Abstract

In this study, the ground-state geometries and absorption wavelengths of 1-substituted (NO 2 , COOH) phenyl-3,5-diphenylformazans have been determined with density functional theory (DFT) and time-dependent DFT (TD-DFT) by combining polarizable continuum model. The calculations were carried out by using PBE1PBE functional with four basis sets to determine the k max of the UV-visible (UV-vis) spectra for the studied formazans. Comparison of experimental and theoretical results showed that k max of the UV-vis spectra could be reproduced by TD-DFT. The effects of chemical substitution on the UV-vis spectra were analyzed.

Experimental and computational studies on the absorption properties of novel formazan derivatives

“…PBE1PBE 40 method with 6-31G(d) basis set was applied because of its good performance in exploring structures and properties of formazans. 20,41,42 Analysis of the harmonic vibrational frequencies using analytical second derivatives was performed to confirm the minima. Orbital composition analysis with Mulliken partition was carried out using the Multiwfn program (a multifunctional wavefunction analyzer).…”

Synthesis, crystal structure, optical and electrochemical properties of novel diphenylether-based formazan derivatives

“…The geometry optimizations of all synthesized compounds in the gas phase were carried out at the DFT level of theory using PBE1PBE/6-311g (2d,2p)-level basis set. [59][60][61] Relative Gibbs free energies and possible tautomeric forms of each molecule were calculated using the same level of basis set. The results are listed in Tables 5 and 6.…”

Frontiers of Formazans Chemistry: A Review

“…[162] The properties of the formazans have been mostly investigated by UV-visible spectroscopy and theoretical and experimental results have been reported. [163][164][165] Formazan peaks λ max values are generally observed at 410-500nm and may be shifted to 550-600nm based upon the structure. These peaks are due to π-π* electronic transitions in formazan skeleton.…”