LINE-SHAPES OF CHARGE-TRANSFER SPECTRA

The theoretical description of condensed-media line shapes of electronic transitions, as developed in earlier papers, is applied to the charge-transfer (CT) spectra of the complexes mesitylene:tetracyanoethylene (Mes:TCNE) and anthracene:chloranil (AN:CA). Results are compared with those previously published for benzene:iodine (Bz:I2), and the factors which contribute to line broadening (inhomogeneous broadening, the Franck-Condon profile, and donor-acceptor vibrational motion) are discussed. The results of an attempt to determine the contributions to the line shape made by intermolecular orbital couplings are presented. In addition, the Bz:I2 CT spectrum is reinvestigated, and the question of which ionization potential of benzene is involved is addressed. © 1979 American Institute of Physics.