Absolute isotopic composition and atomic weight of neodymium using thermal ionization mass spectrometry.
Synthetic mixtures prepared gravimetrically from highly enriched isotopes of neodymium in the form of oxides of well-defined purity were used to calibrate a thermal ionization mass spectrometer. A new error analysis was applied to calculate the final uncertainty of the atomic weight value. Measurements on natural neodymium samples yielded an absolute isotopic composition of 27.153(19) atomic percent (at.%) 142Nd, 12.173(18) at.% 143Nd, 23.798(12) at.% 144Nd, 8.293(7) at.% 145Nd, 17.189(17) at.% 146Nd, 5.756(8) at.% 148Nd, and 5.638(9) at.% 150Nd, and the atomic weight of neodymium as 144.2415(13), with uncertainties given on the basis of 95% confidence limits. No isotopic fractionation was found in terrestrial neodymium materials.
Zhao
Motian
M
National Research Centre for Certified Reference Materials, Beijing 100013, China. motian_zhao@263.net.cn
Zhou
Tao
T
Wang
Jun
J
Lu
Hai
H
Fang
Xiang
X
Guo
Chunhua
C
Li
Qiuli
Q
Li
Chaofeng
C
D006358:Hot Temperature; D038622:Internationality; D007554:Isotopes / Q000032:analysis* / Q000592:standards*; D008970:Molecular Weight; D009354:Neodymium / Q000032:analysis* / Q000592:standards*; D012016:Reference Values; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods* / Q000592:standards*
D007554:Isotopes; D009354:Neodymium