INFRARED-SPECTRA AND ELECTROOPTICAL PARAMETERS OF SUBSTITUTED ANILINES IN H-BONDED COMPLEXES

The spectra of aniline and mono- and bi-(CH3, F, Cl, Br)-substituted anilines in the free state and in 1:1 complexes with different proton acceptors in CCl4 medium are studied in the region of the stretching vibrations. Spectral characteristics of the absorption bands of amino group stretching vibrations are determined. Within the context of an R-NH2 model with regard to dynamic and electro-optical non-equivalency of amino group NH bonds, the vibrational and electro-optical problems were solved. Valence angles gamma(HNH), and dynamical and electro-optical NH bond parameters were calculated, and a correlation between the bond parameters and spectral properties of the amino group stretching vibrations was established. Our research demonstrates that geometrical, dynamic and electro-optical features of the amino groups of free and H-bonded molecules are highly sensitive to the nature, position and number of substituents in the aniline aromatic ring and also to individual properties of the proton acceptors.