PHOTOPHYSICAL STUDY OF ROSE BENGAL DYE IN AQUEOUS MICELLAR SOLUTION

The absorption and fluorescence spectra of Rose Bengal dye were studied in various solvents. It was found that solvent effects on the absorption wavelength are consistent with the solvatochromic shift. We found a linear relationship with the absorption wavelength of the dye in various solvents. Calculations were used to assign the absorption in the region 540–570nm to a π–π* transition between the HOMO and LUMO of the anion. Experimental ground state and excited state dipole moments were calculated by using the solvatochromatic shifts of absorption and fluorescence spectra .