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a18_CO3_H2O() calculates the 18O/16O fractionation factor between carbonate ion CO3(2-) and water.





Temperature (°C).


Returns the 18O/16O fractionation factor.


$$\alpha^{18}_{CO3(2-)/H2O} = e^{2.39 \times \frac{1000}{T^{2}} - 0.00270}$$

The equation above and in the function is the uncorrected equation in Beck et al. (2005). They experimentally determined the fractionation factor using BaCO3 precipitation experiments. However, they applied the acid fractionation factor of calcite during the data processing and not that of BaCO3. The acid fractionation factor of BaCO3 is not known accurately, which may result in a bias of up to 1‰ in the calculated 1000lna values.


Beck, W. C., Grossman, E. L., & Morse, J. W. (2005). Experimental studies of oxygen isotope fractionation in the carbonic acid system at 15°, 25°, and 40°C. Geochimica et Cosmochimica Acta, 69(14), 3493-3503. doi:10.1016/j.gca.2005.02.003

See also

Other fractionation_factors: a13_CO2g_CO2aq(), a18_CO2acid_c(), a18_CO2aq_H2O(), a18_CO2g_H2O(), a18_H2O_OH(), a18_HCO3_H2O(), a18_c_H2O(), a_A_B()