Dauphas N, Reisberg L, Marty B
Centre de Recherches Pétrographiques et Géochimiques, CNRS UPR 2300, Vandoeuvre-lès-Nancy, France.
Anal Chem. 2001 Jun 1;73(11):2613-6. doi: 10.1021/ac000998g.
A procedure was developed that allows precise determination of molybdenum isotope abundances in natural samples. Purification of molybdenum was first achieved by solvent extraction using di(2-ethylhexyl) phosphate. Further separation of molybdenum from isobar nuclides was obtained by ion chromatography using AG1-X8 strongly basic anion exchanger. Finally, molybdenum isotopic composition was measured using a multiple collector inductively coupled plasma hexapole mass spectrometer. The abundances of molybdenum isotopes 92, 94, 95, 96, 97, 98, and 100 are 14.8428(510), 9.2498(157), 15.9303(133), 16.6787(37), 9.5534(83), 24.1346(394), and 9.6104(312) respectively, resulting in an atomic mass of 95.9304(45). After internal normalization for mass fractionation, no variation of the molybdenum isotopic composition is observed among terrestrial samples within a relative precision on the order of 0.00001-0.0001. This demonstrates the reliability of the method, which can be applied to searching for possible isotopic anomalies and mass fractionation.
开发了一种可精确测定天然样品中钼同位素丰度的方法。首先通过使用磷酸二（2-乙基己基）酯的溶剂萃取实现钼的纯化。然后使用AG1-X8强碱性阴离子交换剂通过离子色谱法进一步将钼与同量异位素分离。最后，使用多接收器电感耦合等离子体六极杆质谱仪测量钼的同位素组成。钼同位素92、94、95、96、97、98和100的丰度分别为14.8428(510)、9.2498(157)、15.9303(133)、16.6787(37)、9.5534(83)、24.1346(394)和9.6104(312)，得出原子质量为95.9304(45)。在对质量分馏进行内部归一化后，在相对精度约为0.00001 - 0.0001的范围内，未观察到陆地样品中钼同位素组成的变化。这证明了该方法的可靠性，可用于寻找可能的同位素异常和质量分馏。
