Computational Studies on Dihalogen Complexes of N-methyl Imidazoline-2-thione and N-methyl Imidazolidine-2-thione

The structural and energy characteristics of N-methyl Imidazoline-2-thione and N-methyl Imidazolidine-2-thione molecular complexes with the dihalogens beta, IBr and ICl have been investigated using quantum mechanical techniques. In all cases the planar geometries have been found to be favoured over the perpendicular structures which present a vertical arrangement of the dihalogen IY axis with respect to the imidazolethione plane. The results also reveal interesting trends regarding the correlation of various properties such as the S-I boning distance, the N-H stretching frequency shifting, the enthalpy of complexation and the interaction between the amidic hydrogen with the electron-acceptor dihalogen ability and the electronegativity of the Y atom.