Er5Ge3: enthalpy of formation

5 accepted literature formation-enthalpy value(s) (experimental 2, model 3); experimental median -95.4 kJ/mol-atom (n = 2); Materials Project -77.425 kJ/mol-atom (mp-aaaaarny); OQMD -77.604 kJ/mol-atom (oqmd-18316).

Systems: Er–Ge

Literature values

Enthalpy of formation of Er5Ge3 reported in the literature (5)
ValuePhase as printedT (K)ClassMethodSystemSourceLocationQuote
-95.6 kJ/mol-atom ± 2Er5Ge3298.15experimentalCalorimeterEr–Ge[1] Achgar 2017
cites Meschel 1997 doi
Table 5, p. 7, row 2
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-95.2 kJ/mol-atom ± 2.7Er5Ge3950experimentalEMFEr–Ge[1] Achgar 2017
cites Sidorko 2008
Table 5, p. 7, row 1
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-91.88 kJ/mol-atomEr5Ge3950modelOptimizationEr–Ge[1] Achgar 2017Table 5, p. 7, row 6
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-91.45 kJ/mol-atomEr5Ge3950modelOptimizationEr–Ge[1] Achgar 2017Table 5, p. 7, row 5
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-75 kJ/mol-atomEr5Ge3modelPredictionEr–Ge[1] Achgar 2017
cites A 1983
Table 5, p. 7, row 3
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Uncertainty budget

Components kept separate, in the value's unit (literature SCHEMA.md, UNCERTAINTY_CALIBRATION.md): effective = max(sqrt(max(printed, reading, method)^2 + composition^2 + conversion^2), scatter). The method floor is the robust between-study scatter of the method class in ORCHID (calibrated) or a documented prior; printed values and printed uncertainties are unchanged.

Uncertainty budget of the literature values of Er5Ge3
ValueUnitPrintedReadingMethod (class, basis)CompositionScatterConversionEffective
-95.6kJ/mol-atom20.053.2 (solution_reaction_calorimetry, calibrated)3.2
-95.2kJ/mol-atom2.70.054.6 (emf, cleaned_below_threshold)4.6
-91.88kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9
-91.45kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9
-75kJ/mol-atom0.053.9 (model_calculated, calibrated)3.9

DFT formation energies

Lowest-energy entries at this composition. Materials Project and OQMD use different energy references and are never averaged. 1 eV/atom = 96.485 kJ/mol-atom.

DFT formation energy of Er5Ge3
SourceEntrykJ/mol-atomeV/atomSpace groupE above hull (kJ/mol-atom)E above hull (eV/atom)Theoretical
Materials Projectmp-aaaaarny-77.425-0.802457P6_3/mcm00no
OQMDoqmd-18316-77.604-0.804316P63/mcm00no

DFT sources: A. Jain et al., Commentary: The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002. doi:10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501-1509; S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010. doi:10.1007/s11837-013-0755-4 (CC BY 4.0);

Sources

  1. Khadija Achgar, Saïd Kardellass, Najim Selhaoui, Lahcen Bouirden, Thermodynamic optimization of the Erbium-Germanium binary system, Journal of Alloys and Compounds 724, 1157-1166 (2017). doi:10.1016/j.jallcom.2017.07.129