Substituent and solvent effects on the photo-physical properties of some coumarin dyes

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Vol. 77; no. 2; pp. 337 - 341
• Main Authors: Zakerhamidi, M.S., Ghanadzadeh, A., Tajalli, H., Moghadam, M., Jassas, M., Hosseini nia, R.
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.10.2010
• Subjects: Absorption; Coloring Agents - chemistry; Coumarin dyes; Coumarins - chemistry; Hydrogen Bonding; Indicators and Reagents - chemistry; Light; Linear solvation energy relationships; Molecular Structure; Orientation polarizability; Solvent polarity scale; Solvents - chemistry; Solvent–solute interactions; Spectrometry, Fluorescence; Solvent–solute interactions; Solvent polarity scale; Coumarin dyes; Linear solvation energy relationships; Orientation polarizability
• ISSN: 1386-1425; 1873-3557
• DOI: 10.1016/j.saa.2009.12.060

Absorption and fluorescence spectra of three coumarin dyes with various substituents and alkyl groups have been recorded in solvents in the range of 200–730 nm. The photo-physical behavior of dissolved dye depends on the nature of its environment, i.e. the solvatochromic behaviors of coumarin dyes and solvent/solute hydrogen bonding interactions can be analyzed by means of linear solvation energy relationships concept proposed by Kamlet and Taft. The intensity, shape, and maximum wavelength of the absorption and fluorescence band of these dyes in solution depend strongly on the solvent–solute interactions and solvent nature. Hydrogen bonding interactions (specific solute–solvent interactions) between these dye–solvent complex and dipolarity/polarizability (non-specific solute–solvent interactions) control reorientation of solvent molecules around the dye.