CaSn: enthalpy of formation
6 accepted literature formation-enthalpy value(s) (experimental 2, model 3, DFT 1); experimental median -70.75 kJ/mol-atom (n = 2); Materials Project -62.533 kJ/mol-atom (mp-aaaaadqg); OQMD -67.837 kJ/mol-atom (oqmd-20943).
Systems: Ca–Sn
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -79.5 kJ/mol-atom ± 10.5 | CaSn | 298.15 | experimental | Ca–Sn | [1] OHNO 2006 cites Kubaschewski 1949 | Table 3, p. 5, row 23 report | ||
| -62 kJ/mol-atom ± 1 | CaSn | 298.15 | experimental | Ca–Sn | [1] OHNO 2006 cites Bouirden 1984 | Table 3, p. 5, row 24 report | ||
| -72 kJ/mol-atom | CaSn | 298.15 | model | Calphad | Ca–Sn | [1] OHNO 2006 | Table 3, p. 5, row 28 report | |
| -70.2455 kJ/mol-atom | CaSn | 298.15 | model | Calphad | Ca–Sn | [1] OHNO 2006 cites Cartigny 2005 | Table 3, p. 5, row 26 report | |
| -63.6393 kJ/mol-atom | CaSn | 298.15 | model | Calphad | Ca–Sn | [1] OHNO 2006 | Table 3, p. 5, row 27 report | |
| -66.3191 kJ/mol-atom | CaSn | 298.15 | DFT | First-principles | Ca–Sn | [1] OHNO 2006 | Table 3, p. 5, row 25 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 |
|---|---|---|---|---|---|---|---|---|
| -79.5 | kJ/mol-atom | 10.5 | 5.000e-5 | 3.5 (unknown, calibrated) | 10.5 | |||
| -62 | kJ/mol-atom | 1 | 5.000e-5 | 3.5 (unknown, calibrated) | 3.5 | |||
| -72 | kJ/mol-atom | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -70.2455 | kJ/mol-atom | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -63.6393 | kJ/mol-atom | 5.000e-5 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -66.3191 | 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-aaaaadqg | -62.533 | -0.648111 | Cmcm | 0 | 0 | no |
| OQMD | oqmd-20943 | -67.837 | -0.703084 | Cmcm | 0 | 0 | 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
- M OHNO, A KOZLOV, R ARROYAVE, Z LIU, R SCHMIDFETZER, Thermodynamic modeling of the Ca–Sn system based on finite temperature quantities from first-principles and experiment, Acta Materialia 54, 4939-4951 (2006). doi:10.1016/j.actamat.2006.06.017