Details

Autor(en) / Beteiligte

• Assonov, Sergey
• Fajgelj, Ales
• Hélie, Jean‐François
• Allison, Colin
• Gröning, Manfred

Titel

Characterisation of new reference materials IAEA‐610, IAEA‐611 and IAEA‐612 aimed at the VPDB δ13C scale realisation with small uncertainty

Ist Teil von

• Rapid communications in mass spectrometry, 2021-04, Vol.35 (7), p.e9014-n/a

Ort / Verlag

Bognor Regis: Wiley Subscription Services, Inc

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Rationale LSVEC, the second anchor Reference Material (RM) for the VPDB δ13C scale realisation, was introduced in 2006. In 2015, its δ13C value was found to be drifting and, in 2017, its use as an RM for δ13C was officially discontinued by IUPAC. New RMs of low uncertainty are needed. This paper describes the preparation and characterisation of IAEA‐610, IAEA‐611 and IAEA‐612 (calcium carbonate, of chemical origin) which shall serve as a set of RMs aimed at anchoring the VPDB scale at negative δ13C values. Methods The preparation and characterisation of IAEA‐610, IAEA‐611 and IAEA‐612 were performed by addressing the contemporary technical requirements for RM production and characterisation (ISO Guide 35:2017). The three RMs were produced in large quantities, and the first batch was sealed into ampoules (0.5 g) to ensure the integrity of the RM during storage; additional batches were sealed for long‐term storage. The most accurate method of CO2 preparation and stable isotope measurements was used, namely carbonate‐H3PO4 reaction under well‐controlled conditions combined with well‐tested stable isotope ratio mass spectrometry. Results The assigned values of δ13C and associated uncertainties are based on a large number of analyses (~10 mg aliquots) performed at IAEA and address all the known uncertainty components. For aliquots down to ~100 μg, the δ13C uncertainty is increased. The uncertainty components considered are as follows: (i) material homogeneity, (ii) value assignment against IAEA‐603, (iii) potential storage effects, (iv) effect of the 17O correction, and (v) mass spectrometer linearity and cross‐contamination memory in the ion source. Conclusions The new RMs IAEA‐610, IAEA‐611 and IAEA‐612 have been characterised on the VPDB δ13C scale in a mutually consistent way. The use of three RMs will allow a consistent realisation of the VPDB δ13C scale with small uncertainty to be established, and to reach metrological compatibility of measurement results over several decades.