作者:Michelle D. Regulacio、Michele H. Pablico、Joan Acay Vasquez、Peter N. Myers、Stuart Gentry、Michael Prushan、Suk-Wah Tam-Chang、Sarah L. Stoll
DOI:10.1021/ic701974q
日期:2008.3.1
We have discovered room temperature photoluminescence in SM3+ and Pr3+ dithiocarbamate complexes. Surprisingly, these complexes exhibit more intense emission than those of the Eu3+, Tb3+, and Dy3+ analogues. The electronic absorption, excitation, and emission spectra are reported for the complexes [Ln(S2CNR2)(3)L] and NH2Et2[Ln(S2CNEt2)(4)], where Ln = Sm, Pr; R = ethyl, butyl, benzyl; and L = 1,10-phenanthroline, 2,2'-bipyridine, and 5-chloro-1,10-phenanthroline. The lowest ligand-localized triplet energy level (T-1) of the complexes are determined from the phosphorescence spectra of analogous La3+ and Gd3+ chelates. The luminescence decay curves were measured to determine the excited-state lifetimes for the Pr3+ and Sm3+ complexes. X-ray crystal structures of Sm((S2CNBu2)-Bu-i)(3)phen, Pr(S2CNEt2)(3)phen, and Pr((S2CNBu2)-Bu-i)(3)phen are also reported.
Praseodymium complexes of 2,2′-bipyridine; the crystal and molecular structures of Pr(bipy)3(NCS)3, Pr(bipy)2(NO3)3, Pr(bipy)2Cl3(OH2)·EtOH and Pr(bipy)(S2CNEt2)3
作者:John F Bower、Simon A Cotton、John Fawcett、Robert S Hughes、David R Russell
DOI:10.1016/s0277-5387(02)01359-1
日期:2003.1
The structures of Pr(biPy)(3)(NCS)(3), Pr(bipy)(2)(NO3)(3), Pr(bipy)(2)Cl-3(OH2).EtOH and Pr(bipy)(S2CNEt2)(3) are reported. Pr(biPY)(3)(NCS)(3) has a monomeric structure with three N-bonded thiocyanates and three bidentate bipyridyl ligands, giving nine-coordinate praseodymium. Praseodymium is eight-coordinate in Pr(bipy)(2)Cl-3(OH2).EtOH and in Pr(bipy)(S2CNEt2)(3) whilst Pr(bipy)(2)(NO3)(3) is isostructural with the La, Nd and Lu analogues, having three bidentate nitrates and two bipyridyl ligands, affording 10-coordinate praseodymium. Factors affecting bond lengths in the compounds are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.