Ag2Er: enthalpy of formation
5 accepted literature formation-enthalpy value(s) (experimental 1, model 2, DFT 2); experimental median -24 kJ/mol-atom (n = 1); Materials Project -32.114 kJ/mol-atom (mp-aaaabswx); OQMD -33.095 kJ/mol-atom (oqmd-1976497).
Systems: Ag–Er
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -24 kJ/mol-atom ± 2.3 | Ag2Er | 298.15 | experimental | Ag–Er | [1] Long 2010 cites Steeb 1968 doi | Table 1, p. 3, row 17 report | ||
| -39 kJ/mol-atom | Ag2Er | model | Ag–Er | [1] Long 2010 cites Niessen 1983 doi | Table 1, p. 3, row 18 report | |||
| -24 kJ/mol-atom ± 2.3 | Ag2Er | model | Ag–Er | [1] Long 2010 cites Steeb 1968 doi | Table 1, p. 3, row 34 report | |||
| -34.119 kJ/mol-atom | Ag2Er | 298.15 | DFT | first-principles calculations | Ag–Er | [1] Long 2010 | Table 1, p. 3, row 16 report | |
| -34.119 kJ/mol-atom | Ag2Er | 298.15 | DFT | first-principles (VASP PAW-GGA) | Ag–Er | [1] Long 2010 | Table 1, p. 3, row 33 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 |
|---|---|---|---|---|---|---|---|---|
| -24 | kJ/mol-atom | 2.3 | 5.000e-4 | 3.5 (unknown, calibrated) | 3.5 | |||
| -39 | kJ/mol-atom | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -24 | kJ/mol-atom | 2.3 | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | |||
| -34.119 | kJ/mol-atom | 5.000e-4 | 8.395 (dft, calibrated) | 8.395 | ||||
| -34.119 | kJ/mol-atom | 5.000e-5 | 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-aaaabswx | -32.114 | -0.332838 | I4/mmm | 0 | 0 | no |
| OQMD | oqmd-1976497 | -33.095 | -0.343003 | Fmmm | 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
- Z.H. Long, Y.J. Yang, S. Jin, H.S. Liu, F. Zheng, Z.P. Jin, Thermodynamic assessments of Ag–Dy and Ag–Er binary systems, Journal of Alloys and Compounds 489, 146-151 (2010). doi:10.1016/j.jallcom.2009.09.036