AsGe: enthalpy of formation

5 accepted literature formation-enthalpy value(s) (experimental 1, model 3, unspecified 1); experimental median -5.5 kJ/mol-atom (n = 1); Materials Project -4.154 kJ/mol-atom (mp-aaaaaodg); OQMD -4.148 kJ/mol-atom (oqmd-15392).

Systems: As–Ge

Literature values

Enthalpy of formation of AsGe reported in the literature (5)
ValuePhase as printedT (K)ClassMethodSystemSourceLocationQuote
-5.5 kJ/mol-atom ± 2.6GeAs298.15experimentalDrop calorimetryAs–Ge[1] Chen 2022
cites Fitzner 1996 doi
Table II, p. 3, row 1
report
-4.481 kJ/mol-atomGeAs298.15modelCALPHADAs–Ge[1] Chen 2022Table II, p. 3, row 5
report
-4.14 kJ/mol-atomGeAs0modelFirst–principlesAs–Ge[1] Chen 2022
cites Saal 2013
Table II, p. 3, row 2
report
-2.98 kJ/mol-atomGeAs0modelFirst–principlesAs–Ge[1] Chen 2022
cites ref. 36
Table II, p. 3, row 3
report
-4.43 kJ/mol-atomGeAs0unspecifiedFirst–principlesAs–Ge[1] Chen 2022Table II, p. 3, row 4
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 AsGe
ValueUnitPrintedReadingMethod (class, basis)CompositionScatterConversionEffective
-5.5kJ/mol-atom2.60.053.2 (solution_reaction_calorimetry, calibrated)3.2
-4.481kJ/mol-atom5.000e-43.9 (model_calculated, calibrated)3.9
-4.14kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9
-2.98kJ/mol-atom0.0053.9 (model_calculated, calibrated)3.9
-4.43kJ/mol-atom0.0054.1 (experimental_unspecified, cleaned_below_threshold)4.1

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 AsGe
SourceEntrykJ/mol-atomeV/atomSpace groupE above hull (kJ/mol-atom)E above hull (eV/atom)Theoretical
Materials Projectmp-aaaaaodg-4.154-0.043056C2/m00no
OQMDoqmd-15392-4.148-0.04299C2/m00no

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. Shanxiong Chen, Jiong Wang, Shangzhao Yu, Biao Hu, Qing Wu, Yong Du, Thermodynamic Modeling of the Ge-X (X = As, Se, S, P) Systems, J. Electron. Mater. 51, 2114-2130 (2022). doi:10.1007/s11664-022-09474-1