CoZr: enthalpy of formation

10 accepted literature formation-enthalpy value(s) (experimental 5, model 5); experimental median -35.8 kJ/mol-atom (n = 1); Materials Project -28.143 kJ/mol-atom (mp-aaaaadjv); OQMD -32.068 kJ/mol-atom (oqmd-1926887).

Systems: Co–Zr

Literature values

Enthalpy of formation of CoZr reported in the literature (10)
Value	Phase as printed	T (K)	Class	System	Source	Location
-43.05 per mol-atom ± 3900	CoZr	1030	experimental	Co–Zr	[1] Zhou 2021 cites Gomozov 1986	Table 3, p. 5, row 13 report
-42.2 per mol-atom ± 1000	CoZr	1512	experimental	Co–Zr	[1] Zhou 2021 cites Gachon 1983 doi	Table 3, p. 5, row 12 report
-35.8 per mol-atom ± 700	CoZr	298.15	experimental	Co–Zr	[1] Zhou 2021 cites Guo 1998 doi	Table 3, p. 5, row 14 report
-35.8 kJ/mol-atom	CoZr	298.15	experimental	Co–Zr	[2] Bratberg 2006 cites Binary 1986	Table 6, p. 5, row 1 report
-28.83 per mol-atom	CoZr	298.15	experimental	Co–Zr	[1] Zhou 2021 cites Ohodnicki 2008 doi	Table 3, p. 5, row 15 report
-60 kJ/mol-atom	CoZr	298.15	model	Co–Zr	[2] Bratberg 2006	Table 6, p. 5, row 3 report
-60 kJ/mol-atom	CoZr	298.15	model	Co–Zr	[2] Bratberg 2006 cites Miedema 1998	Table 6, p. 5, row 2 report
-40.267 per mol-atom	CoZr	1512	model	Co–Zr	[1] Zhou 2021	Table 3, p. 5, row 17 report
-35.694 per mol-atom	CoZr	298.15	model	Co–Zr	[1] Zhou 2021	Table 3, p. 5, row 18 report
-35.326 per mol-atom	CoZr	298.15	model	Co–Zr	[1] Zhou 2021 cites Agraval 2020 doi	Table 3, p. 5, row 16 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 CoZr
Value	Unit	Printed	Reading	Method (class, basis)	Effective
-43.05	per mol-atom	3900	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	3900
-42.2	per mol-atom	1000	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	1000
-35.8	per mol-atom	700	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	700
-35.8	kJ/mol-atom		0.05	3.5 (unknown, calibrated)	3.5
-28.83	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
-60	kJ/mol-atom		0.5	3.9 (model_calculated, calibrated)	3.9
-60	kJ/mol-atom		0.5	3.9 (model_calculated, calibrated)	3.9
-40.267	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
-35.694	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
-35.326	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

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 CoZr
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaaadjv	-28.143	-0.291685	Pm-3m	0	0	no
OQMD	oqmd-1926887	-32.068	-0.33236	Cm	0	0	yes

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

Chenyang Zhou, Hang Wang, Thermodynamic Descriptions of the Co–Zr and Co–Fe–Zr Systems, J. Phase Equilib. Diffus. 42, 77-90 (2021). doi:10.1007/s11669-020-00859-5
Johan Bratberg, Bo Jansson, Thermodynamic evaluation of the C−Co−W−Hf−Zr system for cemented carbides applications, JPED 27, 213-219 (2006). doi:10.1361/154770306x109746

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}
}