Al13Ba7: enthalpy of formation
6 accepted literature formation-enthalpy value(s) (experimental 2, model 3, DFT 1); experimental median -45.93 kJ/mol-atom (n = 2); Materials Project -20.981 kJ/mol-atom (mp-aaaaacxc); OQMD -20.651 kJ/mol-atom (oqmd-10392).
Systems: Al–Ba
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -45.93 kJ/mol-atom | Al13Ba7 | 298.15 | experimental | Al–Ba | [1] Azza 2017 cites Srikanth 1991 doi | Table 4, p. 6, row 5 report | ||
| -45.93 kJ/mol-atom | Al13Ba7 | 298.15 | experimental | Vapor pressure | Al–Ba | [2] Benhafid 2019 cites Srikanth 1991 doi | Table 3, p. 4, row 11 report | |
| -53.874 kJ/mol-atom | Al13Ba7 | model | CALPHAD | Al–Ba | [2] Benhafid 2019 cites Bao 2016 doi | Table 3, p. 4, row 12 report | ||
| -51.72 kJ/mol-atom | Al13Ba7 | model | Al–Ba | [1] Azza 2017 | Table 4, p. 6, row 6 report | |||
| -23.896 kJ/mol-atom | Al13Ba7 | model | CALPHAD | Al–Ba | [2] Benhafid 2019 | Table 3, p. 4, row 10 report | ||
| -21.795 kJ/mol-atom | Al13Ba7 | 0 | DFT | Ab-initio | Al–Ba | [2] Benhafid 2019 | Table 3, p. 4, row 9 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 |
|---|---|---|---|---|---|---|---|---|
| -45.93 | kJ/mol-atom | 0.005 | 3.5 (unknown, calibrated) | 3.5 | ||||
| -45.93 | kJ/mol-atom | 0.005 | 4.2 (kems_vapour, calibrated) | 4.2 | ||||
| -53.874 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -51.72 | kJ/mol-atom | 0.005 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -23.896 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -21.795 | kJ/mol-atom | 5.000e-4 | 8.395 (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.
| Source | Entry | kJ/mol-atom | eV/atom | Space group | E above hull (kJ/mol-atom) | E above hull (eV/atom) | Theoretical |
|---|---|---|---|---|---|---|---|
| Materials Project | mp-aaaaacxc | -20.981 | -0.217451 | P-3m1 | 2.3938 | 0.0248 | no |
| OQMD | oqmd-10392 | -20.651 | -0.214029 | P-3m1 | 2.0448 | 0.0212 | 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
- H. Azza, N. Selhaoui, K. Achgar, Thermodynamic description of the aluminum-barium phase diagram, Eur. Phys. J. Spec. Top. 226, 1143-1150 (2017). doi:10.1140/epjst/e2016-60183-4
- 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