摘要
Among the rare earth elements there are six with even atomic numbers starting from neodymium, which possess atomic weights with poor uncertainties of ±0.02%. The present study aims at making precise mass spectrometric measurement of the six isotopic abundance ratios of samarium, attempting to correct the measured ratio, R<sub>150/152</sub> of samarium, by the known true ratio, R<sub>151/153</sub> of europium, and normalizing the six ratios so as to yield new isotopic abundance values and the atomic weight of samarium, 150.3548±0.0009.
基金
Project supported by the National Natural Science Foundation of China