In Liquid Scintillation Counting, for example, incomplete synthesis of acetylene during lithium carbide preparation may result in a low yield and concurrent fractionation.
Similarly, the transfer of gases in a vacuum system may involve fractionation error if the sample gas is not allowed to equilibrate throughout the total volume.
Important: Reporting conventions using “Conventional Radiocarbon Age” terminology indicate the result has been corrected for isotopic fractionation.– Beta also measures a second δ13C value in an isotope ratio mass spectrometer (IRMS δ13C).
Fractionation also describes variations in the isotopic ratios of carbon brought about by non-natural causes.
For example, samples may be fractionated in the laboratory through a variety of means; incomplete conversion of the sample from one stage to another or from one part of the laboratory to another.
This value is representative of the sample itself and is reported. In comparison, reporting the “AMS δ13C” is misleading and open to misinterpretation.
Radiocarbon users should always be aware whether the δ13C they are using in their research is the IRMS δ13C or the AMS δ13C.