Bi2Rb: enthalpy of formation
8 accepted literature formation-enthalpy value(s) (experimental 2, model 4, DFT 2); experimental median -25.9 kJ/mol-atom (n = 1); Materials Project -31.18 kJ/mol-atom (mp-aaaabikj); OQMD -29.992 kJ/mol-atom (oqmd-647552).
Systems: Bi–Rb
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -25.9 kJ/mol-atom ± 2 | Bi2Rb | 298.15 | experimental | Vapor Pressure Measurements | Bi–Rb | [1] Dziri 2022 cites Voronin 1974 | Table 4, p. 7, row 1 report | |
| -25.9 per mol-atom ± 2 | Bi2Rb | 298.15 | experimental | Bi–Rb | [2] Liu 2013 cites Voronin 1974 | Table 3, p. 4, row 1 report | ||
| -35.5 per mol-atom | Bi2Rb | 298.15 | model | Bi–Rb | [2] Liu 2013 | Table 3, p. 4, row 2 report | ||
| -35.5 kJ/mol-atom | Bi2Rb | model | Calphad | Bi–Rb | [1] Dziri 2022 cites Liu 2013 doi | Table 4, p. 7, row 2 report | ||
| -34.433 kJ/mol-atom | Bi2Rb | model | Calphad | Bi–Rb | [1] Dziri 2022 cites Cao 2014 doi | Table 4, p. 7, row 3 report | ||
| -31.917 kJ/mol-atom | Bi2Rb | model | Calphad | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 4 report | ||
| -35.533 kJ/mol-atom | Bi2Rb | 0 | DFT | Ab-initio LDA | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 6 report | |
| -30.434 kJ/mol-atom | Bi2Rb | 0 | DFT | Ab-initio GGA | Bi–Rb | [1] Dziri 2022 | Table 4, p. 7, row 5 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 |
|---|---|---|---|---|---|---|---|---|
| -25.9 | kJ/mol-atom | 2 | 0.05 | 4.2 (kems_vapour, calibrated) | 4.2 | |||
| -25.9 | per mol-atom | 2 | 0.05 | unit 'per mol-atom' not convertible to kJ/mol-atom | 2 | |||
| -35.5 | per mol-atom | 0.05 | unit 'per mol-atom' not convertible to kJ/mol-atom | unit 'per mol-atom' not convertible to kJ/mol-atom | ||||
| -35.5 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -34.433 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -31.917 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -35.533 | kJ/mol-atom | 5.000e-4 | 8.395 (dft, calibrated) | 8.395 | ||||
| -30.434 | 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-aaaabikj | -31.18 | -0.323161 | Fd-3m | 0 | 0 | no |
| OQMD | oqmd-647552 | -29.992 | -0.310843 | Fd-3m | 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
- 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
- Miao Liu, Changrong Li, Zhenmin Du, Cuiping Guo, Chunju Niu, Thermodynamic assessment of the Bi–Rb binary system, Thermochimica Acta 551, 27-32 (2013). doi:10.1016/j.tca.2012.10.012