Dimer complex UV absorption spectra of some nitrogen heterocycles molecules from atom monopole-dipole interaction model

The ultra violet absorption spectra of the dimeric complex given by the atom monopole-dipole interaction (AMDI) model are presented for indole, carbazole, and 1,3-diazaazulene. A system that qualitatively has the same response as real isolated molecule in UV external field was build up. The structural parameters are optimized using the triple zeta valence polarization standard basis set at the DFT/B3LYP level of theory. Features of electronic transitions obtained from atom monopole-dipole interaction are compared to configuration interaction singles (CIS), Zerner intermediate neglect of differential overlap (ZINDO) and experimental measurements. It is shown that the most stable dimeric conformation in vacuum is obtained from Fraga formalism. The effect of solute-solute interaction on the absorption spectrum is discussed.