MgSm: enthalpy of formation
1 accepted literature formation-enthalpy value(s) (experimental 1); experimental median -3.9 kJ/mol-atom (n = 1); Materials Project -9.611 kJ/mol-atom (mp-aaaaaduk); OQMD -10.074 kJ/mol-atom (oqmd-90153).
Systems: Mg–Sm
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -3.9 kJ/mol-atom | SmMg | 298.15 | experimental | Vapor press. | Mg–Sm | [1] Hampl 2013 cites ref. 1967Ogr | Table 6, p. 10, row 13 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 |
|---|---|---|---|---|---|---|---|---|
| -3.9 | kJ/mol-atom | 0.05 | 4.2 (kems_vapour, calibrated) | 4.2 |
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-aaaaaduk | -9.611 | -0.099615 | Pm-3m | 0 | 0 | no |
| OQMD | oqmd-90153 | -10.074 | -0.104412 | Pm-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
- M. Hampl, C. Blawert, M.R. Silva Campos, N. Hort, Q. Peng, K.U. Kainer et al., Thermodynamic assessment and experimental study of Mg–Gd alloys, Journal of Alloys and Compounds 581, 166-177 (2013). doi:10.1016/j.jallcom.2013.07.042