• Journal of the Korean Chemical Society
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• v.26 no.1
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• pp.24-30
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• 1982

Contact-only (COM) and dipolar-only (DOM) mixtures of the lanthanide shift reagents were prepared based on the Fi and Gi values deduced using individual Ln$(fod)_3$ (Ln = Pr, Nd, Eu, and Yb) and 4-picoline. The $F_i$ and $G_i$ values obtained directly by COM 1 and by DOM 1, which were appropriate mixture of Pr$(fod)_3$ and Eu$(fod)_3$, agreed well with those values obtained by experiments using individual Ln$(fod)_3$ shift reagents. Ei and Gi values obtained directly by COM 2 and by DOM 2, which were mixtures of Nd$(fod)_3$ and Yb$(fod)_3$, deviated from the expected values. The error was traced to the behavior of the ytterbium complexes.

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.433-438
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• 1986

Two new types of NMR shift reagents, one giving dipolar-only and the other giving contact-only shifts, can be prepared simply by mixing two appropriate $Ln(fod)_3$(Ln = Pr, Nd, Eu, and Yb) reagents in certain ratios. The $^1H$ and $^{13}C$ NMR spectra of pyridine-type substrates, quinoline and isoquinoline, whose paramagnetic shifts are normally a composite of contact and dipolar contributions with single lanthanide shift reagents, show the feasibility of this approach.

• Analytical Science and Technology
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• v.28 no.3
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• pp.204-211
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• 2015

Lanthanide complexes have attracted much attention because of their unique light emitting property. The light-emitting efficiencies of europium β-diketonate complexes were compared with those of complexes coordinated by the ligands of amines or phosphine oxides. The results demonstrated that the complexes that were coordinated by phosphine oxides had higher light-conversion performance than those coordinated by amines. The highest light-emitting efficiency was observed when the ligand of trioctylphosphine oxide was coordinated. In order to determine the coordination equivalency of trioctylphosphine oxide in the above complexes, 31P-NMR and their photoluminescence spectra were measured. The findings showed that the europium β-diketonate complex had one or two coordination equivalencies of trioctylphosphine oxide according to the steric hindrance of its original ligand.