title: Hindered intramolecular electron transfer in room-temperature ionic liquid.
abstract: Three perylene tetracarboxylic diimide (PDI) compounds, namely, N,N'- di(2-N'',N''-dimethylamino)ethylperylene-3,4:9,10-tetracarboxylic diimide (1), N,N'-di(2-N'',N''-dimethylamino)propylperylene-3,4:9,10-tetracarboxylic diimide (2), and N,N'- dicyclohexyl-1,7-pyrrolidinylperylene-3,4:9,10-tetracarboxylic diimide (3), have been designed and prepared. Their photophysical properties in room-temperature ionic liquid (RTILs) were studied by steady-state absorption and emission spectra and fluorescence lifetime measurements. The intramolecular photoinduced electron transfer from dimethylamine to PDI in 1 and 2 has been efficiently hindered because of the solvation of RTILs. A two-conformation mechanism for the PET in 1 and 2 is proposed, which explains the results of the fluorescence lifetime measurements well. The solvation of RTILs to 3 resembled that of a normal polar organic solvent with polarity larger than that of DMF.
authors.affiliation: Key Lab of Colloid and Interface Chemistry of Education Ministry, Department of Chemistry, Shandong University, Jinan 250100, China.
authors.forename: Haixia
authors.initials: H
authors.lastname: Wu
authors.forename: Haixia
authors.initials: H
authors.lastname: Wang
authors.forename: Lin
authors.initials: L
authors.lastname: Xue
authors.forename: Yan
authors.initials: Y
authors.lastname: Shi
authors.forename: Xiyou
authors.initials: X
authors.lastname: Li