CoGe2: enthalpy of formation

7 accepted literature formation-enthalpy value(s) (experimental 2, model 5); experimental median -11.8 kJ/mol-atom (n = 1); Materials Project -14.777 kJ/mol-atom (mp-aaaabslp); OQMD -15.207 kJ/mol-atom (oqmd-647051).

Systems: Co–Ge

Literature values

Enthalpy of formation of CoGe2 reported in the literature (7)
Value	Phase as printed	T (K)	Class	System	Source	Location
-11.8 per mol-atom ± 1274	CoGe2	1060	experimental	Co–Ge	[1] Zeng 2019 cites Predel 1979 doi	Table 4, p. 9, row 25 report
-11.8 kJ/mol-atom	CoGe2	1060	experimental	Co–Ge	[2] Dong 2013 cites Predel 1979 doi	Table 6, p. 5, row 17 report
-16.579 per mol-atom	CoGe2	1060	model	Co–Ge	[1] Zeng 2019	Table 4, p. 9, row 27 report
-16.241 per mol-atom	CoGe2	1060	model	Co–Ge	[1] Zeng 2019	Table 4, p. 9, row 26 report
-15.836 kJ/mol-atom	CoGe2	1060	model	Co–Ge	[2] Dong 2013	Table 6, p. 5, row 18 report
-15.343 kJ/mol-atom	CoGe2	298.15	model	Co–Ge	[2] Dong 2013	Table 5, p. 4, row 3 report
-14.874 kJ/mol-atom	CoGe2	298.15	model	Co–Ge	[2] Dong 2013	Table 5, p. 4, row 3 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 CoGe2
Value	Unit	Printed	Reading	Method (class, basis)	Effective
-11.8	per mol-atom	1274	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	1274
-11.8	kJ/mol-atom		5.000e-4	3.5 (unknown, calibrated)	3.5
-16.579	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-16.241	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-15.836	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-15.343	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-14.874	kJ/mol-atom		5.000e-4	3.9 (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 CoGe2
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaabslp	-14.777	-0.153152	Cmce	0	0	no
OQMD	oqmd-647051	-15.207	-0.157609	Cmca	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

Yinping Zeng, Yong Du, Han Li, Peng Zhou, Shuhong Liu, Kaiming Cheng et al., Thermodynamic description and solidified microstructure of the Co-Ge system, Journal of Alloys and Compounds 793, 480-491 (2019). doi:10.1016/j.jallcom.2018.12.205
S.S. Dong, S.G. Liu, X.M. Tao, F.H. Xiao, L.H. Huang, F. Yang et al., Thermodynamic optimization of Co–Ge binary system, Thermochimica Acta 572, 94-100 (2013). doi:10.1016/j.tca.2013.08.026

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735569
R. Arróyave, J. Saal, D. Shin, ORCHID-Parity: DFT-vs-experiment formation-enthalpy benchmark (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735943
R. Arróyave, J. Saal, D. Shin, ORCHID data: umbrella record of the ORCHID datasets (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23736065

Also cite the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work); A. Jain et al., The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002, https://doi.org/10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501, https://doi.org/10.1007/s11837-013-0755-4 and S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010, https://doi.org/10.1038/npjcompumats.2015.10 (CC BY 4.0); G. Kim, S. V. Meschel, P. Nash, W. Chen, Experimental formation enthalpies for intermetallic phases and other inorganic compounds, Scientific Data 4 (2017) 170162, https://doi.org/10.1038/sdata.2017.162; B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, https://doi.org/10.1016/j.calphad.2025.102833 (CC BY 4.0), and the original assessment named in each file. Version 1, machine-extracted: values were read by language-model readers constrained to quote their source and checked automatically, and the release was then audited on the printed pages by adversarial audits, an independent second review of fit-facing records and a preliminary human review of a frozen sample. Flags such as accepted and ESPEI-ready record screening results, not certification; known issues are listed in the release notes.

@misc{orchid_literature_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735569},
  url       = {https://doi.org/10.5281/zenodo.23735569},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_dft_benchmark_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Parity: DFT-vs-experiment formation-enthalpy benchmark}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735943},
  url       = {https://doi.org/10.5281/zenodo.23735943},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_data_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID data: umbrella record of the ORCHID datasets}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23736065},
  url       = {https://doi.org/10.5281/zenodo.23736065},
  note      = {Version 1, machine-extracted}
}