Mixed Excimer Fluorescence; The Importance of Charge-Transfer Interaction

Mixed excimer fluorescence is observed when any one of a variety of aromatic hydrocarbons is added to solutions of 9-cyanoanthracene or 9, 10-dicyanoanthracene. The formation of a mixed excimer appears to be markedly dependent upon the ionization potential of the donor. The emission maxima of the 9, 10-dicyanoanthracene mixed excimers vary linearly with the polarographic oxidation potentials of the donors, a results corresponding to that found for charge-transfer absorption bands. It is concluded that charge-transfer interaction is important in the excimer state.