Cr11Ge8: enthalpy of formation

4 accepted literature formation-enthalpy value(s) (experimental 3, model 1); experimental median -28.6 kJ/mol-atom (n = 3); Materials Project 0.724 kJ/mol-atom (mp-aaabgmwh).

Systems: Cr–Ge

Literature values

Enthalpy of formation of Cr11Ge8 reported in the literature (4)
ValuePhase as printedT (K)ClassMethodSystemSourceLocationQuote
-30.7 kJ/mol-atomCr11Ge81273experimentalCr–Ge[1] Liu 2010
cites Yassin 1999 doi
p. 2
report
The deduced enthalpies of formation for Cr11 Ge8 at 1305 K and 1273 K relative to both liquid components are about -28.6 kJ/mol-atom and -30.7 kJ/mol-atom, respectively.
-28.6 kJ/mol-atomCr11Ge81305experimentalCr–Ge[1] Liu 2010
cites Yassin 1999 doi
p. 2
report
The deduced enthalpies of formation for Cr11 Ge8 at 1305 K and 1273 K relative to both liquid components are about -28.6 kJ/mol-atom and -30.7 kJ/mol-atom, respectively.
-10.92 kJ/mol-atomCr11Ge8298.15experimentalPotentiometric methodCr–Ge[1] Liu 2010
cites Lukashenko 1974
Table 4, p. 7, row 7
report
-16.19 kJ/mol-atomCr11Ge8298.15modelThermodynamic optimizationCr–Ge[1] Liu 2010Table 4, p. 7, row 8
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 Cr11Ge8
ValueUnitPrintedReadingMethod (class, basis)CompositionScatterConversionEffective
-30.7kJ/mol-atom0.053.5 (unknown, calibrated)3.5
-28.6kJ/mol-atom0.053.5 (unknown, calibrated)3.5
-10.92kJ/mol-atom0.0054.6 (emf, cleaned_below_threshold)4.6
-16.19kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9

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 Cr11Ge8
SourceEntrykJ/mol-atomeV/atomSpace groupE above hull (kJ/mol-atom)E above hull (eV/atom)Theoretical
Materials Projectmp-aaabgmwh0.7240.007507Pnma9.06130.0939no

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. Y.Q. Liu, Y. Du, Thermodynamic description of the Cr–Ge system, Calphad 34, 26-35 (2010). doi:10.1016/j.calphad.2009.11.001