Ni2Sm: enthalpy of formation
4 accepted literature formation-enthalpy value(s) (experimental 1, model 3); experimental median -36 kJ/mol-atom (n = 1); Materials Project -35.037 kJ/mol-atom (mp-aaaaacby); OQMD -35.32 kJ/mol-atom (oqmd-17805).
Systems: Ni–Sm
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -36 kJ/mol-atom ± 1 | SmNi2 | 300 | experimental | Direct calorimetry | Ni–Sm | [1] Rahou 2016 cites Borzone 2001 doi | Table 5, p. 6, row 11 report | |
| -37.7 kJ/mol-atom | SmNi2 | model | Prediction | Ni–Sm | [1] Rahou 2016 cites Shilov 1987 | Table 5, p. 6, row 13 report | ||
| -35.9 kJ/mol-atom | SmNi2 | 300 | model | Optimization | Ni–Sm | [1] Rahou 2016 | Table 5, p. 6, row 10 report | |
| -32.9 kJ/mol-atom | SmNi2 | model | Optimization | Ni–Sm | [1] Rahou 2016 cites Su 1998 doi | Table 5, p. 6, row 12 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 |
|---|---|---|---|---|---|---|---|---|
| -36 | kJ/mol-atom | 1 | 0.05 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | |||
| -37.7 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -35.9 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -32.9 | kJ/mol-atom | 0.05 | 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-aaaaacby | -35.037 | -0.363136 | Fd-3m | 0 | 0 | no |
| OQMD | oqmd-17805 | -35.32 | -0.366069 | 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
- Z. Rahou, K. Mahdouk, Thermodynamic reassessment of the Sm–Ni binary system, Journal of Alloys and Compounds 664, 469-475 (2016). doi:10.1016/j.jallcom.2015.12.215