Al8V5: enthalpy of formation
8 accepted literature formation-enthalpy value(s) (experimental 1, model 3, DFT 4); experimental median -34 kJ/mol-atom (n = 1); Materials Project -21.333 kJ/mol-atom (mp-aaacrxsd); OQMD -6.349 kJ/mol-atom (oqmd-1486473).
Systems: Al–V
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -34 kJ/mol-atom | Al8V5 | 298.15 | experimental | Exp | Al–V | [1] Luo 2018 cites Meschel 1994 | Table 3, p. 5, row 7 report | |
| -22.557 kJ/mol-atom | Al8V5 | model | Al–V | [1] Luo 2018 | Table 3, p. 5, row 10 report | |||
| -20.269 kJ/mol-atom | Al8V5 | model | Al–V | [1] Luo 2018 | Table 3, p. 5, row 11 report | |||
| -19.03 kJ/mol-atom | Al8V5 | model | Al–V | [1] Luo 2018 | Table 3, p. 5, row 9 report | |||
| -19.39 kJ/mol-atom | Al8V5 | DFT | DFT | Al–V | [1] Luo 2018 cites ref. 21 | Table 3, p. 5, row 5 report | ||
| -18.19 kJ/mol-atom | Al8V5 | DFT | DFT | Al–V | [1] Luo 2018 cites ref. 21 | Table 3, p. 5, row 6 report | ||
| -18.18 kJ/mol-atom | Al8V5 | DFT | DFT | Al–V | [1] Luo 2018 cites ref. 21 | Table 3, p. 5, row 8 report | ||
| -12.65 kJ/mol-atom | Al8V5 | DFT | DFT | Al–V | [1] Luo 2018 cites ref. 21 | Table 3, p. 5, row 4 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 |
|---|---|---|---|---|---|---|---|---|
| -34 | kJ/mol-atom | 0.05 | 4.1 (experimental_unspecified, cleaned_below_threshold) | 4.1 | ||||
| -22.557 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -20.269 | kJ/mol-atom | 5.000e-4 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -19.03 | kJ/mol-atom | 0.005 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -19.39 | kJ/mol-atom | 0.005 | 8.395 (dft, calibrated) | 8.395 | ||||
| -18.19 | kJ/mol-atom | 0.005 | 8.395 (dft, calibrated) | 8.395 | ||||
| -18.18 | kJ/mol-atom | 0.005 | 8.395 (dft, calibrated) | 8.395 | ||||
| -12.65 | kJ/mol-atom | 0.005 | 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-aaacrxsd | -21.333 | -0.2211 | Cm | 3.3136 | 0.0343 | yes |
| OQMD | oqmd-1486473 | -6.349 | -0.065802 | R-3m | 18.4296 | 0.191 | 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
- Qun Luo, Kang Li, Qian Li, Thermodynamic investigation of phase equilibria in Al–Si–V system, Journal of Materials Science & Technology 34, 1592-1601 (2018). doi:10.1016/j.jmst.2018.01.004