Au2Tm: enthalpy of formation
3 accepted literature formation-enthalpy value(s) (experimental 1, model 1, DFT 1); experimental median -91.6 kJ/mol-atom (n = 1); Materials Project -85.835 kJ/mol-atom (mp-aaaaaavo); OQMD -85.794 kJ/mol-atom (oqmd-1895441).
Systems: Au–Tm
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -91.6 kJ/mol-atom ± 2.3 | Au2Tm | 298.15 | experimental | High temperature direct synthesis calorimetry at 1373 ± 2 K | Au–Tm | [1] Dong 2012 cites Meschel 2004 doi | Table 1, p. 2, row 50 report | |
| -82.7 kJ/mol-atom | Au2Tm | 298.15 | model | CALPHAD assessment | Au–Tm | [1] Dong 2012 | Table 1, p. 2, row 51 report | |
| -59.4 kJ/mol-atom | Au2Tm | 0 | DFT | ab initio | Au–Tm | [1] Dong 2012 | Table 1, p. 2, row 49 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 |
|---|---|---|---|---|---|---|---|---|
| -91.6 | kJ/mol-atom | 2.3 | 0.05 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | |||
| -82.7 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -59.4 | kJ/mol-atom | 0.05 | 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-aaaaaavo | -85.835 | -0.889623 | I4/mmm | 0 | 0 | no |
| OQMD | oqmd-1895441 | -85.794 | -0.889192 | P4mm | 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
- H.Q. Dong, X.M. Tao, T. Laurila, M. Paulasto-Kröckel, Thermodynamic assessment of Au–Ho and Au–Tm binary systems, Calphad 37, 87-93 (2012). doi:10.1016/j.calphad.2012.02.002