Be17Ti2: enthalpy of formation
7 accepted literature formation-enthalpy value(s) (model 5, DFT 2); Materials Project -19.177 kJ/mol-atom (mp-aaacqjph); OQMD -19.201 kJ/mol-atom (oqmd-19076).
Systems: Be–Ti
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -31.3 kJ/mol-atom | αTi2Be17 | model | Be–Ti | [1] Tokunaga 2006 cites Kaufman 1973 | Table 2, p. 2, row 13 report | |||
| -26.4 kJ/mol-atom | αTi2Be17 | model | Be–Ti | [1] Tokunaga 2006 cites Kaufman 1979 doi | Table 2, p. 2, row 14 report | |||
| -24.3 kJ/mol-atom | αTi2Be17 | model | Be–Ti | [1] Tokunaga 2006 | Table 2, p. 2, row 12 report | |||
| -22 kJ/mol-atom | βTi2Be17 | 0 | model | Be–Ti | [1] Tokunaga 2006 | Table 2, p. 2, row 15 report | ||
| -21.4 kJ/mol-atom | αTi2Be17 | 0 | model | Be–Ti | [1] Tokunaga 2006 | Table 2, p. 2, row 12 report | ||
| -22 kJ/mol-atom | βTi2Be17 | DFT | Be–Ti | [1] Tokunaga 2006 | Table 2, p. 2, row 15 report | |||
| -21.4 kJ/mol-atom | αTi2Be17 | DFT | Be–Ti | [1] Tokunaga 2006 | Table 2, p. 2, row 12 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 |
|---|---|---|---|---|---|---|---|---|
| -31.3 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -26.4 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -24.3 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -22 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -21.4 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -22 | kJ/mol-atom | 0.05 | 8.395 (dft, calibrated) | 8.395 | ||||
| -21.4 | 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-aaacqjph | -19.177 | -0.198757 | P6_3/mmc | 0 | 0 | no |
| OQMD | oqmd-19076 | -19.201 | -0.199004 | R-3m | 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
- Tatsuya Tokunaga, Hiroshi Ohtani, Mitsuhiro Hasebe, Thermodynamic evaluation of the phase equilibria and glass-forming ability of the Ti−Be system, JPED 27, 83-91 (2006). doi:10.1361/105497106x92844