The oscillator strengths of the absorption spectra for rare earth complexes in different solvents were determined and calculated on the basis of the JuddOfelt theory. The effect of different ligand field strengths on ...The oscillator strengths of the absorption spectra for rare earth complexes in different solvents were determined and calculated on the basis of the JuddOfelt theory. The effect of different ligand field strengths on the oscillator strengths of lanthanide ions is discussed. In plotting the oscillator strengths of the hypersensitive transition of Ho3+, Er3+ against those of Nd3+, the reverse extending lines of the straight lines were found to intersect at a point on the whole. The coordinates of the crosspoint are believed to represent the strength value of the smallest coordinated effect.展开更多
Red frequency-upconversion fluorescence emission is observed in europium（Ⅲ） complex with encapsulating polybenzimidazole tripodal ligands, pumped with 930- and 1070-nm picosecond laser pulses. The lumines- cence of...Red frequency-upconversion fluorescence emission is observed in europium（Ⅲ） complex with encapsulating polybenzimidazole tripodal ligands, pumped with 930- and 1070-nm picosecond laser pulses. The lumines- cence of transition 5D0 →7F2 （612 nm） is induced by two-photon absorption of hypersensitive transitions 7F0 →5D2 （465 nm） and 7F1 →5D1 （535 nm）. Analysis results suggest that the two-photon excitation strength of these hypersensitive transitions is increased dramatically owing to the C3 symmetry of the coordination field.展开更多
In this paper,hypersensitive transitions of Nd(Ⅲ)in Nd(Ⅲ)-β-diketone-neutral ligand ternary coordination compounds(where β-diketone=acetylacetone(AA),benzoylace- tone(BA),dibenzoylmethane(DBM),2-thenoyl trifluoroa...In this paper,hypersensitive transitions of Nd(Ⅲ)in Nd(Ⅲ)-β-diketone-neutral ligand ternary coordination compounds(where β-diketone=acetylacetone(AA),benzoylace- tone(BA),dibenzoylmethane(DBM),2-thenoyl trifluoroacetone(TTA);neutral ligand=pyri- dine(Py),α,α'-dipyridyl(Dipy),phenanthroline(Phen)are studied and their intensities are given through dynamic coupling model.The results are in agreement with those observed and caleulated using Judd-Ofelt equation.It may be seen that the dynamic coupling mechanism provides major contribution to the intensity of hypersensitive transition.On the other hand,in order to get the intensity of ~4I_(9/2)→~4G_(5/2) transition,the absorption spectra in 560—610 nm have been decomposed into threo peaks by nonlinear fitting with Lorentzian and Gaussian funetion and the“pure”intensities of hypersensitive transitions have been obtained, which are agreeable to those computed by Judd-Ofelt method and dynamic coupling model.展开更多
文摘The oscillator strengths of the absorption spectra for rare earth complexes in different solvents were determined and calculated on the basis of the JuddOfelt theory. The effect of different ligand field strengths on the oscillator strengths of lanthanide ions is discussed. In plotting the oscillator strengths of the hypersensitive transition of Ho3+, Er3+ against those of Nd3+, the reverse extending lines of the straight lines were found to intersect at a point on the whole. The coordinates of the crosspoint are believed to represent the strength value of the smallest coordinated effect.
基金supported by the National Natural Science Foundation of China (No. 20903120)the Project of shandong Provincial Higher Educational Science and Technology Program (No. J10LA10)the Doctoral Research Foundation of Qufu Normal University
文摘Red frequency-upconversion fluorescence emission is observed in europium（Ⅲ） complex with encapsulating polybenzimidazole tripodal ligands, pumped with 930- and 1070-nm picosecond laser pulses. The lumines- cence of transition 5D0 →7F2 （612 nm） is induced by two-photon absorption of hypersensitive transitions 7F0 →5D2 （465 nm） and 7F1 →5D1 （535 nm）. Analysis results suggest that the two-photon excitation strength of these hypersensitive transitions is increased dramatically owing to the C3 symmetry of the coordination field.
基金Project supported by the National Natural Science Foundation of China.
文摘In this paper,hypersensitive transitions of Nd(Ⅲ)in Nd(Ⅲ)-β-diketone-neutral ligand ternary coordination compounds(where β-diketone=acetylacetone(AA),benzoylace- tone(BA),dibenzoylmethane(DBM),2-thenoyl trifluoroacetone(TTA);neutral ligand=pyri- dine(Py),α,α'-dipyridyl(Dipy),phenanthroline(Phen)are studied and their intensities are given through dynamic coupling model.The results are in agreement with those observed and caleulated using Judd-Ofelt equation.It may be seen that the dynamic coupling mechanism provides major contribution to the intensity of hypersensitive transition.On the other hand,in order to get the intensity of ~4I_(9/2)→~4G_(5/2) transition,the absorption spectra in 560—610 nm have been decomposed into threo peaks by nonlinear fitting with Lorentzian and Gaussian funetion and the“pure”intensities of hypersensitive transitions have been obtained, which are agreeable to those computed by Judd-Ofelt method and dynamic coupling model.
