title: Polar and low polar solvents media effect on dipole moments of some diazo Sudan dyes.
abstract: Absorption and fluorescence spectra of three Sudan dyes (SudanIII, SudanIV and Sudan black B) were recorded in various solvents with different polarity in the range of 300-800nm, at room temperature. The solvatochromic method was used to investigate dipole moments of these dyes in ground and excited states, in different media. The solvatochromic behavior of these substances and their solvent-solute interactions were analyzed via solvent polarity parameters. Obtained results express the effects of solvation on tautomerism and molecular configuration (geometry) of Sudan dyes in solvent media with different polarity. Furthermore, analyze of solvent-solute interactions and value of ground and excited states dipole moments suggests different forms of resonance structures for Sudan dyes in polar and low-polar solvents.
authors.affiliation: Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran. Electronic address: Zakerhamidi@tabrizu.ac.ir.
authors.forename: M S
authors.initials: MS
authors.lastname: Zakerhamidi
authors.affiliation: Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran.
authors.forename: Sh
authors.initials: Sh
authors.lastname: Golghasemi Sorkhabi
authors.affiliation: Department of Applied Chemistry, Faculty of Sciences, University of Mohaghegh Ardabili, P.O. Box 56199-11367, Ardabil, Iran; Department of Chemistry, Sharif University of Technology, Tehran 11155-9516, Iran.
authors.forename: A N
authors.initials: AN
authors.lastname: Shamkhali
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D012997:Solvents
keywords: Diazo Sudan dye; Dipole moment; Intramolecular charge-transfer; Solvent polarity; Solvent–solute interaction; Tautomeric resonance structure