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New Guidelines for d13C Measurements



T Coplen, W A. Brandt, M Gehre, Manfred Groning, HAJ Meijer, Blaza Toman, Jennifer R. Verkouteren


Consistency of 13C measurements can be improved 39-47% by anchoring the 13C scale with two isotopic referencematerials differing substantially in 13C/12C. It isrecommended that 13C values of both organic andinorganic materials be measured and expressed relativeto VPDB (Vienna Peedee belemnite) on a scale normalizedby assigning consensus values of -46.6 to L-SVEClithium carbonate and +1.95 to NBS 19 calciumcarbonate. Uncertainties of other reference material valueson this scale are improved by factors up to two ormore, and the values of some have been notably shifted:the 13C of NBS 22 oil is -30.03 .
Analytical Chemistry
78 No 7


Coplen, T. , Brandt, W. , Gehre, M. , Groning, M. , Meijer, H. , Toman, B. and Verkouteren, J. (2006), New Guidelines for d13C Measurements, Analytical Chemistry (Accessed December 2, 2023)
Created March 31, 2006, Updated October 12, 2021