title: Molecular distortion effect on ff-emission in a Pr(III) complex with 4,7-diphenyl-1,10-phenanthroline.
abstract: The electronic and structural behaviour of a Pr(III) complex with 4,7-diphenyl-1,10-phenanthroline, [Pr(bathophen)(2)(NO(3))(3)], is investigated with respect to the effect of configuration changes on the Pr(III) centre. [Pr(bathophen)(2)(NO(3))(3)] luminesces from the excited states of the ligand and the metal ion. The fluorescence, ff-emission ((1)D(2)-->(3)H(4)), and phosphorescence bands appear at 394, 608.2 and 482 nm, respectively, in the solid state. In acetonitrile, the complex also shows multiple emissions. From the time-resolved emission and the lifetime measurements, the excitation energy-transfer in [Pr(bathophen)(2)(NO(3))(3)] is clarified, that is, the upper excited triplet level of the ligand acts as an energy donor, while the (1)D(2) levels of Pr(III) is the acceptor. Additionally, the emission phenomena of the complex can be modified by molecular distortion, particularly by rotation of the phenyl groups in the ligand.
authors.affiliation: Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama-Gakuin University, 5-10-1 Fuchinobe, Sagamihara, Kanagawa 229-8558, Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Ishii
authors.forename: Shinobu
authors.initials: S
authors.lastname: Kishi
authors.forename: Hideki
authors.initials: H
authors.lastname: Ohtsu
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Iimori
authors.forename: Takakazu
authors.initials: T
authors.lastname: Nakabayashi
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ohta
authors.forename: Naoto
authors.initials: N
authors.lastname: Tamai
authors.forename: Milan
authors.initials: M
authors.lastname: Melnik
authors.forename: Miki
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Shigesato