Hf3Si2: enthalpy of formation

1 accepted literature formation-enthalpy value(s) (experimental 1); experimental median -80 kJ/mol-atom (n = 1); Materials Project -74.298 kJ/mol-atom (mp-aaaaadcz); OQMD -77.301 kJ/mol-atom (oqmd-647083).

Systems: Hf–Si

Literature values

Enthalpy of formation of Hf3Si2 reported in the literature (1)
ValuePhase as printedT (K)ClassMethodSystemSourceLocationQuote
-80 kJ/mol-atom ± 4.7Hf3Si21473experimentalHf–Si[1] Zhao 2000
cites Topor 1990 doi
Table 3, p. 3, row 9
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.

Uncertainty budget of the literature values of Hf3Si2
ValueUnitPrintedReadingMethod (class, basis)CompositionScatterConversionEffective
-80kJ/mol-atom4.70.053.5 (unknown, calibrated)4.7

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.

DFT formation energy of Hf3Si2
SourceEntrykJ/mol-atomeV/atomSpace groupE above hull (kJ/mol-atom)E above hull (eV/atom)Theoretical
Materials Projectmp-aaaaadcz-74.298-0.770051P4/mbm00no
OQMDoqmd-647083-77.301-0.801176P4/mbm00no

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

  1. J. -C. Zhao, B. P. Bewlay, M. R. Jackson, Q. Chen, Hf-Si binary phase diagram determination and thermodynamic modeling, JPE 21, 40-45 (2000). doi:10.1361/105497100770340408