CrB: enthalpy of formation
4 accepted literature formation-enthalpy value(s) (model 4); Materials Project -50.189 kJ/mol-atom (mp-aaaaaaka); OQMD -49.899 kJ/mol-atom (oqmd-5878).
Systems: B–Cr
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -45 kJ/mol-atom | CrB | model | Calculated | B–Cr | [1] Campbell 2002 cites ref. 41 | Table 4, p. 6, row 17 report | ||
| -39.9 kJ/mol-atom | CrB | model | Assessed | B–Cr | [1] Campbell 2002 cites ref. 42 | Table 4, p. 6, row 2 report | ||
| -39.4 kJ/mol-atom | CrB | model | Assessed | B–Cr | [1] Campbell 2002 cites ref. 16 | Table 4, p. 6, row 7 report | ||
| -37.8 kJ/mol-atom | CrB | model | Assessed | B–Cr | [1] Campbell 2002 | Table 4, p. 6, row 12 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 | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -39.9 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -39.4 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -37.8 | 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-aaaaaaka | -50.189 | -0.520177 | Cmcm | 0.8963 | 0.0093 | no |
| OQMD | oqmd-5878 | -49.899 | -0.517167 | Cmcm | 0.9327 | 0.0097 | 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
- C.E. Campbell, U.R. Kattner, Assessment of the Cr-B system and extrapolation to the Ni-Al-Cr-B quaternary system, Calphad 26, 477-490 (2002). doi:10.1016/s0364-5916(02)00058-5