The role of \u3c0\u3c3 17 state in intramolecular electron-transfer dynamics of 4-dimethylaminobenzonitrile and related molecules

Evidence is presented which indicates that the photoinduced intramolecular charge transfer (ICT) in 4-dimethylaminobenzonitrile proceeds by a new mechanism in which \u3c0\u3c3C 61 N 17 state is the intermediate of a consecutive process that takes the initially excited \u3c0\u3c0 17 state to the fully charge-separated ICT state. The absence of the ICT-state formation in 4-aminobenzonitrile is attributed to the smaller electron-donor strength of the amino group relative to the dimethylamino group, which hinders the \u3c0\u3c3 17\u2192ICT charge-shift reactionPeer reviewed: YesNRC publication: Ye