Si3W5: enthalpy of formation
5 accepted literature formation-enthalpy value(s) (experimental 3, model 2).
Systems: Si–W
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -138 kJ/mol (basis unstated) | W5Si3 | 298.15 | experimental | Mass spectrometry | Si–W | [1] Li 2013 cites Kematick 1993 doi | Table 3, p. 3, row 4 report | |
| -135 kJ/mol (basis unstated) | W5Si3 | 298.15 | experimental | Knudsen effusion | Si–W | [1] Li 2013 cites Chart 1975 doi | Table 3, p. 3, row 3 report | |
| -133 kJ/mol (basis unstated) ± 25 | W5Si3 | 298.15 | experimental | Electromotive force | Si–W | [1] Li 2013 cites Fujiwara 2005 doi | Table 3, p. 3, row 5 report | |
| -145 kJ/mol (basis unstated) | W5Si3 | model | Calculated | Si–W | [1] Li 2013 cites Vahlas 1989 doi | Table 3, p. 3, row 6 report | ||
| -136 kJ/mol (basis unstated) | W5Si3 | model | Calculated | Si–W | [1] Li 2013 | Table 3, p. 3, row 7 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 |
|---|---|---|---|---|---|---|---|---|
| -138 | kJ/mol (basis unstated) | 0.5 | 33.6 (kems_vapour, calibrated) | 33.6 | ||||
| -135 | kJ/mol (basis unstated) | 0.5 | 33.6 (kems_vapour, calibrated) | 33.6 | ||||
| -133 | kJ/mol (basis unstated) | 25 | 0.5 | 36.8 (emf, cleaned_below_threshold) | 36.8 | |||
| -145 | kJ/mol (basis unstated) | 0.5 | 31.2 (model_calculated, calibrated) | 31.2 | ||||
| -136 | kJ/mol (basis unstated) | 0.5 | 31.2 (model_calculated, calibrated) | 31.2 |
Sources
- Yan Li, Changrong Li, Zhenmin Du, Cuiping Guo, Thermodynamic optimization of the Nb–Si–W ternary system, Calphad 43, 112-123 (2013). doi:10.1016/j.calphad.2013.04.004