CoCr: enthalpy of formation
1 accepted literature formation-enthalpy value(s) (experimental 1); experimental median 6.77 kJ/mol-atom (n = 1); Materials Project 14.816 kJ/mol-atom (mp-aaacfmex); OQMD 2.922 kJ/mol-atom (oqmd-1484947).
Systems: Co–Cr
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| 6.77 kJ/mol-atom | CoCr | 473 | experimental | Co–Cr | [1] Liu 2015 cites ref. 67 | p. 9 report | However, Downie and Arslan [67] measured the formation enthalpy of one σCoCr sample close to the composition of the end-member σ-(Co)8(Cr)18(Cr)4 at 473 K and found ΔfH = 6.77 kJ/mol-atom. |
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 |
|---|---|---|---|---|---|---|---|---|
| 6.77 | kJ/mol-atom | 0.005 | 3.5 (unknown, calibrated) | 3.5 |
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-aaacfmex | 14.816 | 0.153561 | Pm-3m | 14.8163 | 0.1536 | yes |
| OQMD | oqmd-1484947 | 2.922 | 0.030289 | P4/mmm | 3.4822 | 0.0361 | 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
- Xuan L. Liu, Thomas Gheno, Bonnie B. Lindahl, Greta Lindwall, Brian Gleeson, Zi-Kui Liu, First-Principles Calculations, Experimental Study, and Thermodynamic Modeling of the Al-Co-Cr System, PLoS ONE 10, e0121386 (2015). doi:10.1371/journal.pone.0121386