This paper relates the quantum-mechanical equilibrium isotopic fractionation correction to the radiocarbon dating method by Eq. 9, and also shows the significant influence of temperature on the method. It is suggested that the correction is a function of the frequencies and temperature of a specific sample and these two variables can be evaluated theoretically by the ab initio quantum calculations and experimentally by analyzing the clumped-isotope ratios in it, respectively. This paper also suggests that the C-14/C-12 ratio in the atmosphere in geological time can be calculated by Eq. 10. 

Publication name	JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY　Volume: 292 　Issue: 1 　Pages: 335-338　 APR 2012
Author(s)	Yuan, Jie; Liu, Yun
Corresponding author	YUAN Jie  xiaojie_hengyao@126.com  1. Chinese Acad Sci, State Key Lab Ore Deposit Geochem, Inst Geochem, Guiyang, Guizhou, Peoples R China  2. Chinese Acad Sci, Grad Univ, Beijing 100039, Peoples R China

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