CoGa3: enthalpy of formation
6 accepted literature formation-enthalpy value(s) (experimental 2, model 2, DFT 2); experimental median -37 kJ/mol-atom (n = 2); Materials Project -25.895 kJ/mol-atom (mp-aaaabekt); OQMD -25.771 kJ/mol-atom (oqmd-29254).
Systems: Co–Ga
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -45 kJ/mol-atom | CoGa3 | 298.15 | experimental | Co–Ga | [1] Gröbner 1999 cites Predel 1975 doi | Table 1, p. 2, row 25 report | ||
| -29 kJ/mol-atom | CoGa3 | 1100 | experimental | Co–Ga | [1] Gröbner 1999 cites Th 1982 | Table 1, p. 2, row 27 report | ||
| -29 kJ/mol-atom | CoGa3 | 298.15 | model | Co–Ga | [1] Gröbner 1999 | Table 1, p. 2, row 26 report | ||
| -28.666 kJ/mol-atom | CoGa3 | 298.15 | model | CALPHAD model | Co–Ga | [2] Chari 2010 | Table 2, p. 4, row 9 report | |
| -32.4 kJ/mol-atom | CoGa3 | 298.15 | DFT | first-principles DFT | Co–Ga | [2] Chari 2010 | Table 2, p. 4, row 8 report | |
| -25.9 kJ/mol-atom | CoGa3 | 298.15 | DFT | first-principles DFT | Co–Ga | [2] Chari 2010 | Table 2, p. 4, 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 |
|---|---|---|---|---|---|---|---|---|
| -45 | kJ/mol-atom | 0.5 | 3.5 (unknown, calibrated) | 3.5 | ||||
| -29 | kJ/mol-atom | 0.5 | 3.5 (unknown, calibrated) | 3.5 | ||||
| -29 | kJ/mol-atom | 0.5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -28.666 | kJ/mol-atom | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -32.4 | kJ/mol-atom | 5.000e-5 | 3.929 (dft, calibrated) | 3.929 | ||||
| -25.9 | kJ/mol-atom | 5.000e-5 | 3.929 (dft, calibrated) | 3.929 |
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-aaaabekt | -25.895 | -0.268388 | P4_2/mnm | 0 | 0 | no |
| OQMD | oqmd-29254 | -25.771 | -0.267098 | P42/mnm | 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
- J. Gröbner, R. Wenzel, G. G. Fischer, R. Schmid-Fetzer, Thermodynamic calculation of the binary systems M-Ga and investigation of ternary M-Ga-N phase equilibria (M=Ni, Co, Pd, Cr), JPE 20, 615-625 (1999). doi:10.1361/105497199770340608
- Arpita Chari, Andres Garay, Raymundo Arróyave, Thermodynamic remodeling of the Co–Ga system, Calphad 34, 189-195 (2010). doi:10.1016/j.calphad.2010.02.004