PbYb2: enthalpy of formation
4 accepted literature formation-enthalpy value(s) (experimental 3, model 1); experimental median -66 kJ/mol-atom (n = 3); OQMD -54.999 kJ/mol-atom (oqmd-17936).
Systems: Pb–Yb
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -67 kJ/mol-atom ± 3 | PbYb2 | 298.15 | experimental | Direct calorimeter | Pb–Yb | [1] Idbenali 2009 cites Sommer 1995 doi | Table 4, p. 6, row 2 report | |
| -66 kJ/mol-atom ± 5 | PbYb2 | 298.15 | experimental | Solution calorimeter | Pb–Yb | [1] Idbenali 2009 cites Sommer 1995 doi | Table 4, p. 6, row 1 report | |
| -58.2 kJ/mol-atom ± 3 | PbYb2 | 298.15 | experimental | Knudsen data | Pb–Yb | [1] Idbenali 2009 cites Schiffman 1982 doi | Table 4, p. 6, row 3 report | |
| -59.99 kJ/mol-atom | PbYb2 | model | Optimization | Pb–Yb | [1] Idbenali 2009 | Table 4, p. 6, row 4 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 |
|---|---|---|---|---|---|---|---|---|
| -67 | kJ/mol-atom | 3 | 0.5 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | |||
| -66 | kJ/mol-atom | 5 | 0.5 | 3.2 (solution_reaction_calorimetry, calibrated) | 5 | |||
| -58.2 | kJ/mol-atom | 3 | 0.05 | 4.2 (kems_vapour, calibrated) | 4.2 | |||
| -59.99 | kJ/mol-atom | 0.005 | 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 |
|---|---|---|---|---|---|---|---|
| OQMD | oqmd-17936 | -54.999 | -0.570026 | Pnma | 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, Thermodynamic description of the Pb–Yb binary system, Calphad 33, 570-575 (2009). doi:10.1016/j.calphad.2009.05.001