Theoretical Study of the Exciplex Formation in an m-MTDATA–BPHEN OLED
By N. O. Dubinets, I. D. Krysko, and A. Ya. Freidzon
The formation of charge-transfer (CT) exciplexes in m-MTDATA–BPhen (4,4′,4»-tris[(3-methylphenyl)phenylamino]-triphenylamine)–bathophenanthroline) donor-acceptor pair is studied using density functional theory (DFT) and multireference quantum chemistry. It is shown that the lowest excited singlet S1 and one of the low-lying triplets have the CT character, while the lowest triplet is localized on the BPhen molecule, which agrees with the experimental fluorescence and phosphorescence data. A multireference treatment agrees with the DFT calculations and shows that the CT character of the exciplex states in such donor-acceptor systems is not an artifact of the functional.
