Selected thermodynamic data for auxiliary compounds and complexes

Table IV-1 Selected thermodynamic data for auxiliary compounds and complexes adopted in the NEA-TDB project, including the CODATA Key Values [89COX/WAG]. All ionic species listed in this table are aqueous species. Unless noted otherwise, all data refer to 298.15 K and a pressure of 0.1 MPa and, for aqueous species, a standard state of infinite dilution (/ = 0). The uncertainties listed below each value represent total uncertainties and correspond in principle to the statistically defined 95% confidence interval. Values in bold typeface are CODATA Key Values and are taken directly from Ref [89COX/WAG] without further evaluation. Values obtained from internal calculation, cf. footnotes (a) and (b), are rounded at the third digit after the decimal point. Systematically, all the values are presented with three digits after the decimal point, regardless of the significance of these digits. The reference listed for each entry in this table indicates the NEA-TDB Review where the corresponding data have been adopted as NEA-TDB auxiliary data. The data presented in this table are available on computer media from the OECD Nuclear Energy Agency.

Table 1V-1 Selected thermodynamic data for auxiliary compounds and complexes..61...

This chapter presents the chemical thermodynamic data for auxiliary compounds and complexes which are used within the NEA s TDB project. Most of these auxiliary species are used in the evaluation of the recommended selenium data in Table lll-l, Table II1-2, and Table III-3. It is therefore essential to always use these auxiliary data in conjunction with the selected data for selenium. The use of other auxiliary data can lead to inconsistencies and erroneous results. Additional auxiliary data used in this review are found in Appendix E, Table E-2 cf. Section II.7). 

Chapter IV contains, for auxiliary compounds and complexes that do not contain selenium, a table of the thermodynamic data for individual species (Table IV-1) and a table of reaction data (Table IV-2). Most of these values are the CODATA Key Values [89COX/WAG]. The selection of the remaining auxiliary data is discussed in [92GRE/FUG], and other preceding volumes of this series. As just mentioned, Appendix E contains a table. Table E-1, of the adopted thermodynamic data for individual selenium compounds calculated with auxiliary data not contained in Chapter IV. The non-TDB auxiliary data, usually from [82WAG/EVA], are presented in Table E-2 and the evaluations are discussed in Chapter V and Appendix A. 

Table lV-2 Selected thermodynamic data for reactions involving auxiliary compounds and complexes.74... 

Although the focus of this review is on thorium, it is necessaiy to use data on a number of other species during the evaluation process that lead to the recommended data. These auxiliary data are taken both from the publication of CODATA Key Values [1989COX/WAG] and from the evaluation of additional auxiliary data in the other volumes of this series detailed above, and their use is recommended by this review. Care has been taken that all the selected thermodynamic data at standard conditions cf. Section II.3) and 298.15 K are internally consistent. For this purpose, special software has been developed at the NEA Data Bank that is operational in conjunction with the NEA-TDB data base system, cf. Section 11.6. In order to maintain consistency in the apphea-tion of the values selected by this review, it is essential to use these auxiliary data when calculating equilibrium constants involving thorium compounds and complexes. 

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