The electronic absorption profiles of 3-cyano-1,5-diarylformazans were recorded in different organic solvents having different polarities. Both macroscopic and microscopic aspects were contemplated to determine the influence of various solute-solvent interactions upon absorption spectral shifts. The effects of solvent polarity on the absorbance profiles of the compounds were evaluated. The multiple linear regression techniques were employed to evaluate Kamlet-Taft coefficients which proved to be instrumental in estimating the contribution of each type of interaction towards spectral shift profiles. It was deduced that the compounds under consideration possessed positive solvatochromism (Bathochromic shifts) owing to the non-specific solute –solvent interactions.
Formazans, Solvatochromism, Linear regression method, Kamlet-Taft parameters