The spectral interference on the rare earth impurities caused by La, Ce and Yb matrix were investigated Within the spectrum windows of RE impurities, the total number of interfering lines generated by La. Ce and Yb were less than that had ever been reported, and some spectrum lines not yet reported were observed when the concentration of those matrices mcreased. The multicomponent spectral fitting (MSF) could effectively corrected the spectral interference, so the detection limits of the rare earth impurities were improved significantly after the correction, but the detection limits did not yet reach the level in the absence of La,Ce and Yb. The permissible mass concentration of matrix wass 1 000～2 000 μg/mL when the impurity concentration was 0. 100 μg/mL. The concentrations were accordingly decreased with the decreasing impurities concentration. During the process for the establishment of MSF model, the impurity concentration should be 100 times of its detection limit,the matrix concentration should be close to its concentration in the sample. Data collections for the MSF model and sample should be carried out in a same experiment under the same experimental conditions.%考察了La、Ce和Yb等基体元素对稀土杂质元素测定的光谱干扰.在杂质元素谱线窗口内,La、Ce和Yb所产生的干扰线总数量比文献报导的少,且当基体元素浓度增大时,在杂质元素谱线窗口内出现一些未曾报道过的谱线.经多元光谱拟合(MSF)法校正,基体元素的光谱干扰得到有效消除,杂质元素的检出限明显降低,但仍达不到没有La、Ce和Yb时的水平.当测定质量浓度为0.100μg/mL杂质元素时允许质量浓度为1 000～2 000μg/mL基体元素存在,当被测的杂质浓度进一步降低时允许基体元素的最高浓度也随之降低.建立MSF模型时,应使建模溶液中杂质元素浓度是这些元素检出限的100倍,基体元素浓度接近实际样品中基体的存在量,MSF建模数据与样品测定数据还须在同一实验条件下完成.
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