Quality Criteria

All data included in the thermodynamic reference database are assigned identifiers for "source", "quality", "category", and "class" as is described below. This shall guide the user when applying THEREDA data to specific application cases. Namely, such information helps to compute complex systems with sparse data and disputed sets of chemical species. It also permits an estimation of consequences of uncertain system understanding or numerical data.

Data Source

-1	Internally calculated
0	By definition / convention fixed value
1	Critical data collection with external review (e. g. CODATA, NEA-TDB, PSI-TDB-Report)
2	Internationally acknowledged review article (e. g. in IUPAC Solubility Data Series, Am. J. Sci. or Coord. Chem. Rev.)
3	Article in a peer-reviewed journal
4	Institutional report, Book, Ph.D. thesis, THEREDA-Journal (or similar publications, all without international or external review)
5	Internal source not available to the public, but available to editors of THEREDA
6	Data source not yet entered (to be done)

Quality Level

-1	Internally calculated
0	By definition / convention fixed value
1	Recommended datum (A model value that has been reviewed and recommended by the THEREDA team and has been shown in tests to be capable of reproducing experimental results.)
2	Supplemental/provisional datum (A model value that can be used for modeling with certain limitations, but for which no better value is available, or whose omission would lead to significantly worse results.)
3	Questionable datum (uncertain model for speciation, uncertain auxiliary data), but nevertheless suitable and necessary for the description of experimental data
4	(abandoned)
5	(abandoned)
6	Data quality not yet entered (to be done)

Data Category

F	formation data
FR	based on formation- and reaction-type data
NA	not applicable
R	reaction data

Data Classes for formation data (F)

-1	Internally calculated from formation data
0	Formation data, by definition or convention
1	Value based upon experimental formation data
2	Chemical analogue value, based upon experimental formation data
3	Estimated value, based upon founded correlations and models for formation data
4	Experimental formation data, not consistently derived with data and speciation model in THEREDA but being checked in calculations against experimental data
5	(abandoned)
6	Formation data, dataclass has not yet been assigned

Data Classes for reaction data (R)

-1	Internally calculated from reaction data
0	Reaction data, by definition or convention
1	Value based upon experimental reaction data
2	Chemical analogue value, based upon experimental reaction data
3	Estimated value, based upon founded correlations and models for reaction data
4	Experimental reaction data, not consistently derived with data and speciation model in THEREDA but being checked in calculations against experimental data
5	(abandoned)
6	Experimental reaction data, dataclass has not yet been assigned

Data Classes for interaction parameters

-1	Internally calculated
0	By definition / convention fixed value
1	Value based upon experimental data
2	Chemical analogue value
3	Estimated value, based upon founded correlations and models
4	Experimental data, not consistently derived with data and speciation model in THEREDA, but being checked in calculations against experimental data
5	(abandoned)
6	dataclass has not yet been assigned

Addional elements for quality assurance

• All data included in THEREDA are assigned, if possible, an uncertainty.

• All data included in THEREDA must be internally consistent.

• Dependencies between data and parameter, which are crucial for internal consistency, must be annotated and visible for the user.

• As far as possible, selection of data shall be accounted for in attached documents, available for the user.

• Parameter files made available from contributors to the THEREDA-project have to undergo a series of pre-defined test calculations.