AlIr: enthalpy of formation
3 accepted literature formation-enthalpy value(s) (experimental 1, DFT 2); experimental median -118 kJ/mol-atom (n = 1); Materials Project -92.527 kJ/mol-atom (mp-aaaaacun); OQMD -91.306 kJ/mol-atom (oqmd-10480).
Systems: Al–Ir
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -118 kJ/mol-atom | B2-AlIr | 298.15 | experimental | Al–Ir | [1] Abe 2008 cites Ode 2005 doi | Table 2, p. 3, row 20 report | ||
| -92.8 kJ/mol-atom ± 1.8 | AlIr | DFT | Al–Ir | [2] JIANG 2006 cites Jung 1992 | Table 1, p. 2, row 4 report | |||
| -91.9 kJ/mol-atom | AlIr | 0 | DFT | First-principles | Al–Ir | [2] JIANG 2006 | Table 1, p. 2, row 3 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 |
|---|---|---|---|---|---|---|---|---|
| -118 | kJ/mol-atom | 0.5 | 3.5 (unknown, calibrated) | 3.5 | ||||
| -92.8 | kJ/mol-atom | 1.8 | 0.05 | 8.395 (dft, calibrated) | 8.395 | |||
| -91.9 | kJ/mol-atom | 0.05 | 8.395 (dft, calibrated) | 8.395 |
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-aaaaacun | -92.527 | -0.958978 | Pm-3m | 0 | 0 | no |
| OQMD | oqmd-10480 | -91.306 | -0.94632 | 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
- T. Abe, C. Kocer, M. Ode, H. Murakami, Y. Yamabe-Mitarai, K. Hashimoto et al., Thermodynamic re-assessment of the Al–Ir system, Calphad 32, 686-692 (2008). doi:10.1016/j.calphad.2008.09.014
- C JIANG, B GLEESON, A combined first-principles/CALPHAD modeling of the Al–Ir system, Acta Materialia 54, 4101-4110 (2006). doi:10.1016/j.actamat.2006.03.058