@misc{oai:nagoya.repo.nii.ac.jp:00018232,
 author = {Kawabe, Iwao},
 month = {Jun},
 note = {The logarithmic stability constants of (1:1) lanthanide(III)-EDTA complex formation, logK(Ln-EDTA), have been reported by polarography, radiotracer-cation exchange, and potentiomery with different ion-selective electrodes. The polarographic data (Schwarzenbach et al.,1954) with uncertainties less than 0.1 for all Ln but Ho are the experimental basis to put forward the Gd-break and convex tetrad effect of logK(Ln-EDTA). Nevertheless, the data for each logK(Ln-EDTA) by the different methods are variable in a range of ± 0.5 or more, although their series changes are fairly parallel. Apparently the polarographic data can never be assessed by the other methods, but we found that all the reported data except those by the radiotracer-cation exchange need further corrections when the standardized condition of T=298.15 K (25°C) and ionic strength μ=0.1 is chosen with assuming that logK(Cu-EDTA)=18.80 (20°C) and logK(Pb-EDTA)=18.04 (20°C). After the corrections and the subsequent normalization of logK(Y-EDTA)=17.62, all the five data sets of logK(Ln-EDTA) by the different methods converge within 2σ(mean) errors less than 0.9 % for all Ln. Here are accepted the converged values and their 2σ(mean) errors as the experimental logK(Ln-EDTA) ones and uncertainties. The Gd-break and convex tetrad effect certainly exist in logK(Ln-EDTA) beyond the experimental uncertainty, but the observed convex tetrad effect in the light Ln series appears less obvious than in the heavy Ln one. The slightly asymmetrical tetrad effect is possibly due to the hydration changes of Ln-EDTA and ligh Ln3+(aq) series.},
 title = {Stability constants of lanthanide(III)-EDTA complex formation and Gd-break with tetrad effect in their series variation},
 year = {2014}
}