Cr2N: enthalpy of formation
2 accepted literature formation-enthalpy value(s) (model 2); Materials Project -48.833 kJ/mol-atom (mp-aaaaamzs); OQMD -43.69 kJ/mol-atom (oqmd-12301).
Systems: Cr–N
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -43.1 kJ/mol-atom | ε(Cr2N) | 298.15 | model | Cr–N | [1] Frisk 1991 | Table I, p. 6, row 7 report | ||
| 41.8 kJ/mol-atom | ε(Cr2N) | 298.15 | model | Cr–N | [1] Frisk 1991 cites Chase 1985 | Table I, p. 6, row 5 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 |
|---|---|---|---|---|---|---|---|---|
| -43.1 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| 41.8 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 |
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-aaaaamzs | -48.833 | -0.506117 | P-31m | 0 | 0 | no |
| OQMD | oqmd-12301 | -43.69 | -0.452821 | P-31m | 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
- Karin Frisk, A thermodynamic evaluation of the Cr-N, Fe-N, Mo-N and Cr-Mo-N systems, Calphad 15, 79-106 (1991). doi:10.1016/0364-5916(91)90028-i