Ca2Sb: enthalpy of formation
2 accepted literature formation-enthalpy value(s) (model 1, DFT 1); Materials Project -91.218 kJ/mol-atom (mp-aaaaaort); OQMD -86.636 kJ/mol-atom (oqmd-1641).
Systems: Ca–Sb
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -76.94 kJ/mol-atom | Ca2Sb | 298.15 | model | Ca–Sb | [1] Qin 2015 | Table 3, p. 3, row 8 report | ||
| -86.47 kJ/mol-atom | Ca2Sb | 0 | DFT | Ca–Sb | [1] Qin 2015 | Table 3, p. 3, row 7 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 |
|---|---|---|---|---|---|---|---|---|
| -76.94 | kJ/mol-atom | 0.005 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -86.47 | kJ/mol-atom | 0.005 | 9.966 (dft, calibrated) | 9.966 |
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-aaaaaort | -91.218 | -0.945408 | I4/mmm | 0 | 0 | no |
| OQMD | oqmd-1641 | -86.636 | -0.897921 | I4mm | 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
- Song Qin, Shuhong Liu, Cong Zhang, Jinghua Xin, Yao Wang, Yong Du, Thermodynamic modeling of the Ca–In and Ca–Sb systems supported with first-principles calculations, Calphad 48, 35-42 (2015). doi:10.1016/j.calphad.2014.10.008