Ge8V11: enthalpy of formation
7 accepted literature formation-enthalpy value(s) (experimental 3, model 3, unspecified 1); experimental median -46.6 kJ/mol-atom (n = 3); Materials Project -33.7 kJ/mol-atom (mp-aaacqgbd).
Systems: Ge–V
Literature values
| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---|---|---|---|---|---|---|---|---|
| -51.6 kJ/mol-atom | V11Ge8 | 1301.15 | experimental | Calorimetry | Ge–V | [1] Yuan 2011 cites Conclusions | Table 3, p. 2, row 5 report | |
| -46.6 kJ/mol-atom | V11Ge8 | 1073.15 | experimental | emf | Ge–V | [1] Yuan 2011 cites Eremenko 1976 | Table 3, p. 2, row 9 report | |
| -45.5 kJ/mol-atom | V11Ge8 | 298.15 | experimental | KEMS | Ge–V | [1] Yuan 2011 cites Zarembo 2000 doi | Table 3, p. 2, row 3 report | |
| -46.5 kJ/mol-atom | V11Ge8 | 298.15 | model | Calculated | Ge–V | [1] Yuan 2011 cites Wang 2008 doi | Table 3, p. 2, row 17 report | |
| -46.1 kJ/mol-atom | V11Ge8 | 298.15 | model | Calculated | Ge–V | [1] Yuan 2011 | Table 3, p. 2, row 21 report | |
| -39.9 kJ/mol-atom | V11Ge8 | 298.15 | model | Calculated | Ge–V | [1] Yuan 2011 cites Smith 1981 doi | Table 3, p. 2, row 13 report | |
| -45.5 kJ/mol-atom | V11Ge8 | unspecified | Ge–V | [1] Yuan 2011 | Table 3, p. 2, row 23 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 |
|---|---|---|---|---|---|---|---|---|
| -51.6 | kJ/mol-atom | 0.05 | 3.2 (solution_reaction_calorimetry, calibrated) | 3.2 | ||||
| -46.6 | kJ/mol-atom | 0.05 | 4.6 (emf, cleaned_below_threshold) | 4.6 | ||||
| -45.5 | kJ/mol-atom | 0.05 | 4.2 (kems_vapour, calibrated) | 4.2 | ||||
| -46.5 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -46.1 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -39.9 | kJ/mol-atom | 0.05 | 3.9 (model_calculated, calibrated) | 3.9 | ||||
| -45.5 | kJ/mol-atom | 0.05 | 3.5 (unknown, calibrated) | 3.5 |
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-aaacqgbd | -33.7 | -0.349275 | Pnma | 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
- Xiaoming Yuan, Weihua Sun, Yoonsung Chung, Honghui Xu, Shuhong Liu, Yong Du et al., Heat contents of the intermetallics V3Ge and V5Ge3 and thermodynamic modeling of the Ge–V system, Thermochimica Acta 513, 100-105 (2011). doi:10.1016/j.tca.2010.11.018