五磷酸钆中Eu3+的光谱

本文对GdP5O14:Eu3+(GdPP:Eu,x:0～1)。晶体的紫外可见吸收、激发光谱、荧光光谱、红外吸收光谱和结构进行了测定和分析。给出了GdPP中Eu3+离子的能级图。讨论了Gd3+—Eu3+离子间的能量转移和猝灭。

SPECTRA OF Eu3+ IN Gdpp SINGLE CRYSTALS

There have probably been more spectrascopic investigations involving Eu3+ reported in the last few years than those of any other Ianthanide.This reflects, of course, the importance of Eu3+-activated phosphors and the interest in Eu3+-based lasers. The volume of work is more remarkable when one realizes that practically all of these investigations are concerned with transitions or fluorescence from several 5D level in the visible region of spectra.This paper reports some results of such an investigation. The growth of GdP5O14(GdPP):Eu3+ single crystals was studied by hydrothermal method.The excitation, emission,absorption and infrared spectra of the crystals wers measured at room temperature and analyzed. Most of the observed emissions and absorptions can be uniquely assigned in terms of specific transition between levels in the 4f shell of Eu3+ ions, and conversely most of predicted transition were obverved.The symmetry-determined electric and magnetic dipole selection rules for the C2, site symmetry are quite well for Eu3+ ions to obey. The strongest absorption at 394nm and the weak sharp band at 361nm could immediately be assigned to transition from 7F0 to 5L6 and 5D4, respectively. The 7F0-5D3 transition was placed at 4l3nm.The bands at 462nm and 522nm identified by their close correlation with transition observed for Eu3+ in the GdPP:Eu crystals are assigned for 7F0-5D2 and 5D1 as has been shown experimentally that the intensity of band at 522nm (7F0-5D1) arises entirely via the magnetic dipole mechanism.