MgB6: enthalpy of formation
5 accepted literature formation-enthalpy value(s) (experimental 5); experimental median -13.39 kJ/mol-atom (n = 2); OQMD 0.227 kJ/mol-atom (oqmd-1454656).
Systems: B–Mg
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -15.5 per mol-atom ± 2.1 | MgB6 | 298.15 | experimental | Vap. p. | B–Mg | [1] Balducci 2005 | Table 2, p. 4, row 15 report | |
| -13.4 per mol-atom | MgB6 | 298.15 | experimental | calorimetry | B–Mg | [1] Balducci 2005 | Table 2, p. 4, row 17 report | |
| -13.4 per mol-atom ± 0.6 | MgB6 | 298.15 | experimental | calorimetry | B–Mg | [1] Balducci 2005 | Table 2, p. 4, row 16 report | |
| -13.39 kJ/mol-atom ± 0.6 | MgB6 | 298.15 | experimental | calorimetry | B–Mg | [2] Liu 2001 cites Jansson 1984 | Table 2, p. 2, row 6 report | |
| -13.39 kJ/mol-atom ± 0.3 | MgB6 | 298.15 | experimental | calorimetry | B–Mg | [2] Liu 2001 cites Sundman 1985 doi | Table 2, p. 2, row 9 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 |
|---|---|---|---|---|---|---|---|---|
| -15.5 | per mol-atom | 2.1 | 0.05 | unit 'per mol-atom' not convertible to kJ/mol-atom | 2.1 | |||
| -13.4 | 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 | ||||
| -13.4 | per mol-atom | 0.6 | 0.05 | unit 'per mol-atom' not convertible to kJ/mol-atom | 0.6 | |||
| -13.39 | kJ/mol-atom | 0.6 | 0.005 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | |||
| -13.39 | kJ/mol-atom | 0.3 | 0.005 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 |
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 |
|---|---|---|---|---|---|---|---|
| OQMD | oqmd-1454656 | 0.227 | 0.002357 | Pm-3m | 13.4941 | 0.1399 | 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
- G. Balducci, S. Brutti, A. Ciccioli, G. Gigli, P. Manfrinetti, A. Palenzona et al., Thermodynamics of the intermediate phases in the Mg–B system, Journal of Physics and Chemistry of Solids 66, 292-297 (2005). doi:10.1016/j.jpcs.2004.06.063
- Zi-Kui Liu, Yu Zhong, D.G. Schlom, X.X. Xi, Qi Li, Computational thermodynamic modeling of the Mg-B system, Calphad 25, 299-303 (2001). doi:10.1016/s0364-5916(01)00050-5