Investigation of solvent effects on UV-vis absorption spectra of dihydroxybenzene derivatives by solvatochromic parameters.

The solvatochromism of dihydroxybenzene derivatives as probes in 18 solvents were investigated in the UV-vis spectra. The position, intensity and shape of absorption bands change with various solvent nature. These changes were rationalized by solvatochromic parameters such as alpha, beta, ET(30), DN and AN using multiple linear regression (MLR) method. The studied dihydroxibenzene derivatives show negative solvatochromism and the correlation coefficients of derived equations by MLR method were obtained in the range 0.974-0.996. The linear solvation energy relationship parameters of the backward regression were applied to the Kamlet and Taft equation for the interaction of these three probes and solvents. The best LSER equation for these three probes, and the LSER parameters of backward regression with their mean effects and the regression coefficient have been calculated.