BiRb: enthalpy of formation
3 accepted literature formation-enthalpy value(s) (model 1, DFT 2); Materials Project -32.944 kJ/mol-atom (mp-aaaabuaj); OQMD -34.733 kJ/mol-atom (oqmd-1798865).
Systems: Bi–Rb
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -35.975 kJ/mol-atom | BiRb | model | Calphad | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 7 report | ||
| -38.131 kJ/mol-atom | BiRb | 0 | DFT | Ab-initio LDA | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 9 report | |
| -35.056 kJ/mol-atom | BiRb | 0 | DFT | Ab-initio GGA | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 8 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 |
|---|---|---|---|---|---|---|---|---|
| -35.975 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -38.131 | kJ/mol-atom | 5.000e-4 | 8.395 (dft, calibrated) | 8.395 | ||||
| -35.056 | 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-aaaabuaj | -32.944 | -0.34144 | P2_1/c | 0 | 0 | no |
| OQMD | oqmd-1798865 | -34.733 | -0.359983 | P212121 | 0 | 0 | yes |
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
- F. Dziri, Y. Djaballah, E. Belbacha, A. Belgacem Bouzida, Thermodynamic Reassessment of the Bi-Rb System Supported by Ab-Initio Calculations, J. Phase Equilib. Diffus. 43, 382-392 (2022). doi:10.1007/s11669-022-00968-3