【摘要】 研究了Nd(TTA)3螯合物溶于二甲基甲酰胺溶剂的光谱性质,溶液中所有氢未置换为氘.测量了这种溶液体系的吸收谱、荧光谱和荧光寿命.在898和1058nm波长处观察到明显的Nd3+荧光特征峰.用Judd-Ofelt理论对吸收谱进行分析计算,得到了三个强度参数Ωt(t=2,4,6)分别为Ω2=4·9×10-20cm2,Ω4=5·1×10-20cm2和Ω6=2·5×10-20cm2.利用强度参数计算了4F3/2能级与4I9/2和4I11/2之间的跃迁强度Sed、自发辐射系数Aed以及荧光分支比β等,估算了4F3/2能级的辐射跃迁寿命τr=682μs.实测1058和898nm波长处荧光寿命τ大约为460和505μs,因此荧光量子效率分别高达0·67和0·74.荧光量子效率高表明Nd3+在这种溶液中无辐射跃迁比较弱;强度参数Ω2比较大,表明Nd3+在溶液中具有不对称配位场环境,不对称的配位场环境可大大促进Nd3+吸收激发能量.光谱质量因子Ω4/Ω6>1,使得898nm的辐射强于1058nm的辐射.更多还原

【Abstract】 Tris-thenoyltrifluroacetonate of Nd 3+ has been prepared and dissolved in DMF solation with very high concentration, and the contained hydrogen has not been substituted by deuterium. The absorption spectrum, emission spectrum, and fluorescence lifetime of the solution were measured. Very obvious characteristic fluorescence peaks were observed at 898 and 1058 nm. Based on Judd-Ofelt theory, three intensity parameters were obtained: Ω₂=4.9×10 -20 cm² , Ω₄=5.1×10 -20 cm² and Ω₆=2.5×10 -20 cm². Line strengths S cal , oscillator strengths f cal , radiative transition probabilities A ed , radiative lifetimes τ_r and branch ratios β were calculated too. The measured lifetime τ of 1058 nm peak is 460 μs, and that of 898 nm 505 μs. Comparison between theoretically computed radiative lifetime τ_r （682 μs） and the measured lifetime indicates that the non-radiative transition probability of the solution is very low and the fluorescence quantum efficiency very high. High values of three intensity parameters prove the high asymmetric surroundings of Nd 3+ , which is important for Nd 3+ to absorb the excitation energy. Spectropic quality factor Ω₄/Ω₆>1 makes radiation at 898 nm stronger than at 1058 nm.更多还原