Al2Se3: enthalpy of formation
5 accepted literature formation-enthalpy value(s) (experimental 2, model 1, DFT 2); experimental median -110.95 kJ/mol-atom (n = 2); Materials Project -108.385 kJ/mol-atom (mp-aaaaarha); OQMD -82.526 kJ/mol-atom (oqmd-1376246).
Systems: Al–Se
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -113.4 kJ/mol-atom | Al2Se3 | 298.15 | experimental | Direct synthesis calorimetry | Al–Se | [1] Shi 2019 cites Kapustinskii 1951 | Table 3, p. 3, row 10 report | |
| -108.5 kJ/mol-atom | Al2Se3 | 298.15 | experimental | Combustion calorimetry | Al–Se | [1] Shi 2019 cites Schneider 1954 doi | Table 3, p. 3, row 11 report | |
| -107.7 kJ/mol-atom | Al2Se3 | 298.15 | model | CALPHAD | Al–Se | [1] Shi 2019 | Table 3, p. 3, row 14 report | |
| -81.72 kJ/mol-atom | Al2Se3 | 0 | DFT | DFT | Al–Se | [1] Shi 2019 cites The 2019 | Table 3, p. 3, row 12 report | |
| -81.24 kJ/mol-atom | Al2Se3 | 0 | DFT | DFT | Al–Se | [1] Shi 2019 cites The 2019 | Table 3, p. 3, row 13 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 |
|---|---|---|---|---|---|---|---|---|
| -113.4 | kJ/mol-atom | 0.05 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | ||||
| -108.5 | kJ/mol-atom | 0.05 | 1 (combustion_calorimetry, cleaned_below_threshold) | 1 | ||||
| -107.7 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -81.72 | kJ/mol-atom | 0.005 | 9.966 (dft, calibrated) | 9.966 | ||||
| -81.24 | kJ/mol-atom | 0.005 | 9.966 (dft, calibrated) | 9.966 |
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-aaaaarha | -108.385 | -1.12333 | Cc | 0 | 0 | no |
| OQMD | oqmd-1376246 | -82.526 | -0.85532 | I41md | 0 | 0 | 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
- Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019). doi:10.1007/s11669-019-00733-z