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 a nilines in the free state and in 1:1 complexes with different proton a cceptors in CCl4 medium are studied in the region of the stretching vi brations. Spectral characteristics of the absorption bands of amino gr oup stretching vibrations are determined. Within the context of an R-N H2 model with regard to dynamic and electro-optical non-equivalency of amino group NH bonds, the vibrational and electro-optical problems we re solved. Valence angles gamma(HNH), and dynamical and electro-optica l NH bond parameters were calculated, and a correlation between the bo nd parameters and spectral properties of the amino group stretching vi brations 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 num ber of substituents in the aniline aromatic ring and also to individua l properties of the proton acceptors.