Spectroscopic studies of molecular interactions involving aniline and substituted aniline donors and chloranil as an electron acceptor in a binary solvent mixtures

摘要

Charge-transfer complexes of chloranil acceptor with aniline and substituted anilines as donors were studied in binary solvent mixtures of different composition of benzene and dichloromethane (by volume) at room temperature.The stoichio-metry of the complexes was established to be 1 : 1.For this purpose,optical data were subjected to the form of the Rose-Drago equation for 1 : 1 equilibria.The stoichiometry was also tested by other methods such as Scott,Scatchard in addition to Bensi-Hildebrand method.The formation constant (k_c) and molar absorptivities (epsilon_(ganna)) of complexes were determined by least square method.Linear relationship was found between oscillator strength (f) and refractive index function n~2-1/ 2n~2 + 1.The values of hv_(CT) were correlated with ionization potential of the donor and a linear relationship was obtained with a slope approximating to unity allowing the determination of the energy of interaction in the excited state.Charge-transfer (CT) band maxima of complexes show red shifts in passing from primary -> secondary -> tertiary amines.