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Revised δ34S Reference Values for IAEA Sulfur Isotope Reference Materials S-2 and S-3



Jacqueline L. Mann, Robert D. Vocke Jr., William R. Kelly


Revised δ34S reference values with associated expanded uncertainties (95% confidence interval (C.I.)) are presented for he sulfur isotope reference materials IAEA-S-2 (22.62 ±0.16{0/00}). These revised values are determined using two relative-difference measurement techniques, gas source isotope ratio mass spectrometry (GIRMS) and double-spike multi-collector thermal ionization mass spectromety (MC-TIMS). Gas analyses have traditionally been considered the most robust for relative isotopic difference measurements of sulfur. The double-spike MC-TIMS technique provides an independent method for value-assignment validation and produces revised valuesthat are both unbiased and more precise than previous value assignments. Unbiased δ34S values are required to anchor the positive and negative end members of the sulfur delta (δ) scale because they are the basis for reporting both δ34S values and the derived mass-independent {Δ}33S and {Δ}36S values.
Rapid Communications in Mass Spectrometry


sulfur, reference materials, IAEA-S-2, IAEA-S-3, MCTIMS, mass-independent


Mann, J. , Vocke, R. and Kelly, W. (2009), Revised &#948;<sup>34</sup>S Reference Values for IAEA Sulfur Isotope Reference Materials S-2 and S-3, Rapid Communications in Mass Spectrometry, [online], (Accessed April 20, 2024)
Created February 7, 2009, Updated February 19, 2017