Ba3Ge4: enthalpy of formation

3 accepted literature formation-enthalpy value(s) (model 2, DFT 1); Materials Project -54.983 kJ/mol-atom (mp-aaaaaope); OQMD -54.784 kJ/mol-atom (oqmd-24528).

Systems: Ba–Ge

Literature values

Enthalpy of formation of Ba3Ge4 reported in the literature (3)
ValuePhase as printedT (K)ClassMethodSystemSourceLocationQuote
-59.09 kJ/mol-atomα- Ba3Ge4modelCALPHADBa–Ge[1] Benhafid 2019Table 3, p. 4, row 25
report
-58.599 kJ/mol-atomβ- Ba3Ge4modelCALPHADBa–Ge[1] Benhafid 2019Table 3, p. 4, row 27
report
-58.317 kJ/mol-atomβ- Ba3Ge40DFTAb-initioBa–Ge[1] Benhafid 2019Table 3, p. 4, row 26
report

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 Ba3Ge4
ValueUnitPrintedReadingMethod (class, basis)CompositionScatterConversionEffective
-59.09kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9
-58.599kJ/mol-atom5.000e-43.9 (model_calculated, calibrated)3.9
-58.317kJ/mol-atom5.000e-48.395 (dft, calibrated)8.395

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 Ba3Ge4
SourceEntrykJ/mol-atomeV/atomSpace groupE above hull (kJ/mol-atom)E above hull (eV/atom)Theoretical
Materials Projectmp-aaaaaope-54.983-0.569861Cmmm00no
OQMDoqmd-24528-54.784-0.567801Cmmm00no

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. R. Benhafid, A. Belgacem Bouzida, Y. Djaballah, A. Candan, A. İyigör, G. Uğur, Thermodynamic Modeling of the Al-Ba and Ba-Ge Systems Supported by First-Principles Calculations, J. Phase Equilib. Diffus. 40, 195-205 (2019). doi:10.1007/s11669-019-00714-2