BaPb: enthalpy of formation
5 accepted literature formation-enthalpy value(s) (experimental 2, model 3); experimental median -74.15 kJ/mol-atom (n = 2); Materials Project -56.755 kJ/mol-atom (mp-aaaabdum); OQMD -56.392 kJ/mol-atom (oqmd-10853).
Systems: Ba–Pb
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -75.3 kJ/mol-atom ± 12 | Ba0.5Pb0.5 | 300 | experimental | Ba–Pb | [1] Idbenali 2007 cites Kubaschewski 1949 | Table 5, p. 9, row 15 report | ||
| -73 kJ/mol-atom ± 2 | Ba0.5Pb0.5 | 300 | experimental | Ba–Pb | [1] Idbenali 2007 cites Conclusion | Table 5, p. 9, row 12 report | ||
| -101 kJ/mol-atom | Ba0.5Pb0.5 | 300 | model | Ba–Pb | [1] Idbenali 2007 cites F 2007 | Table 5, p. 9, row 13 report | ||
| -76.223 kJ/mol-atom | Ba0.5Pb0.5 | 300 | model | Ba–Pb | [1] Idbenali 2007 | Table 5, p. 9, row 11 report | ||
| -74.454 kJ/mol-atom | Ba0.5Pb0.5 | 300 | model | Ba–Pb | [1] Idbenali 2007 | Table 5, p. 9, row 14 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.
| Value | Unit | Printed | Reading | Method (class, basis) | Composition | Scatter | Conversion | Effective |
|---|---|---|---|---|---|---|---|---|
| -75.3 | kJ/mol-atom | 12 | 5.000e-4 | 3.5 (unknown, calibrated) | 12 | |||
| -73 | kJ/mol-atom | 2 | 5.000e-4 | 3.5 (unknown, calibrated) | 3.5 | |||
| -101 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -76.223 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -74.454 | kJ/mol-atom | 5.000e-4 | 3.9 (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.
| Source | Entry | kJ/mol-atom | eV/atom | Space group | E above hull (kJ/mol-atom) | E above hull (eV/atom) | Theoretical |
|---|---|---|---|---|---|---|---|
| Materials Project | mp-aaaabdum | -56.755 | -0.588222 | Cmcm | 0 | 0 | no |
| OQMD | oqmd-10853 | -56.392 | -0.584463 | Cmcm | 0 | 0 | no |
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
- M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007). doi:10.1016/j.calphad.2007.04.003