ZrO2: enthalpy of formation

16 accepted literature formation-enthalpy value(s) (experimental 6, model 9, unspecified 1); experimental median -366 kJ/mol-atom (n = 1); Materials Project -367.957 kJ/mol-atom (mp-aaaaaefy); OQMD -350.528 kJ/mol-atom (oqmd-3278).

Systems: O–Zr

Literature values

Enthalpy of formation of ZrO2 reported in the literature (16)
Value	Phase as printed	T (K)	Class	Method	System	Source	Location
-1100.92 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	experimental		O–Zr	[1] Wang 2004 cites Huber 1964 doi	Table 3, p. 6, row 3 report
-1100.8 kJ/mol (basis unstated)	ZrO2	298.15	experimental	Combustion calorimetry	O–Zr	[2] CHEN 2004 cites Huber 1964	Table 2, p. 3, row 2 report
-1100.6 kJ/mol (basis unstated)	ZrO2	298.15	experimental	Combustion calorimetry	O–Zr	[2] CHEN 2004 cites Kornilov 1967	Table 2, p. 3, row 3 report
-1100.56 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	experimental		O–Zr	[1] Wang 2004 cites Kornilov 1967	Table 3, p. 6, row 4 report
-1094.1 kJ/mol (basis unstated)	ZrO2	298.15	experimental	Combustion calorimetry	O–Zr	[2] CHEN 2004 cites Humphrey 1954	Table 2, p. 3, row 1 report
-366 kJ/mol-atom	ZrO2	298.15	experimental		O–Zr	[3] Arroyave 2002	Table 2, p. 17, row 2 report
-1101 kJ/mol (basis unstated)	ZrO2	298.15	model	Assessed	O–Zr	[2] CHEN 2004 cites Liang 2001	Table 2, p. 3, row 6 report
-1100.97 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	model		O–Zr	[1] Wang 2004 cites Liang 2001	Table 3, p. 6, row 8 report
-1100.7 kJ/mol (basis unstated)	ZrO2	298.15	model	Assessed	O–Zr	[2] CHEN 2004	Table 2, p. 3, row 7 report
-1100.69 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	model		O–Zr	[1] Wang 2004 cites Chen 2004	Table 3, p. 6, row 10 report
-1100.6 kJ/mol (basis unstated)	ZrO2	298.15	model	Assessed	O–Zr	[2] CHEN 2004 cites Ackermann 1975	Table 2, p. 3, row 4 report
-1100.57 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	model		O–Zr	[1] Wang 2004 cites Du 1992 doi	Table 3, p. 6, row 7 report
-1100.31 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	model		O–Zr	[1] Wang 2004 cites Arroyave 2002 doi	Table 3, p. 6, row 9 report
-1097.46 kJ/mol (basis unstated)	ZrO2	298.15	model	Assessed	O–Zr	[2] CHEN 2004 cites Chase 1985	Table 2, p. 3, row 5 report
-573 kJ/mol-atom	ZrO2		model	Electronegativities	O–Zr	[3] Arroyave 2002	Table 2, p. 17, row 1 report
-1100.57 kJ/mol (basis unstated)	monoclinic ZrO2	298.15	unspecified		O–Zr	[1] Wang 2004 cites Dinsdale 2003	Table 3, p. 6, row 11 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 ZrO2
Value	Unit	Reading	Method (class, basis)	Effective
-1100.92	kJ/mol (basis unstated)	5.000e-4	10.5 (unknown, calibrated)	10.5
-1100.8	kJ/mol (basis unstated)	0.05	3 (combustion_calorimetry, cleaned_below_threshold)	3
-1100.6	kJ/mol (basis unstated)	0.05	3 (combustion_calorimetry, cleaned_below_threshold)	3
-1100.56	kJ/mol (basis unstated)	5.000e-4	10.5 (unknown, calibrated)	10.5
-1094.1	kJ/mol (basis unstated)	0.05	3 (combustion_calorimetry, cleaned_below_threshold)	3
-366	kJ/mol-atom	5.000e-4	3.5 (unknown, calibrated)	3.5
-1101	kJ/mol (basis unstated)	0.5	11.7 (model_calculated, calibrated)	11.7
-1100.97	kJ/mol (basis unstated)	5.000e-4	11.7 (model_calculated, calibrated)	11.7
-1100.7	kJ/mol (basis unstated)	0.05	11.7 (model_calculated, calibrated)	11.7
-1100.69	kJ/mol (basis unstated)	5.000e-5	11.7 (model_calculated, calibrated)	11.7
-1100.6	kJ/mol (basis unstated)	0.05	11.7 (model_calculated, calibrated)	11.7
-1100.57	kJ/mol (basis unstated)	5.000e-5	11.7 (model_calculated, calibrated)	11.7
-1100.31	kJ/mol (basis unstated)	5.000e-5	11.7 (model_calculated, calibrated)	11.7
-1097.46	kJ/mol (basis unstated)	5.000e-4	11.7 (model_calculated, calibrated)	11.7
-573	kJ/mol-atom	5.000e-4	3.9 (model_calculated, calibrated)	3.9
-1100.57	kJ/mol (basis unstated)	5.000e-5	10.5 (unknown, calibrated)	10.5

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 ZrO2
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaaaefy	-367.957	-3.81362	P2_1/c	0	0	no
OQMD	oqmd-3278	-350.528	-3.63298	P21/c	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

Chong Wang, Matvei Zinkevich, Fritz Aldinger, On the thermodynamic modeling of the Zr–O system, Calphad 28, 281-292 (2004). doi:10.1016/j.calphad.2004.09.002
M CHEN, B HALLSTEDT, L GAUCKLER, Thermodynamic modeling of the ZrO2–YO1.5 system, Solid State Ionics 170, 255-274 (2004). doi:10.1016/j.ssi.2004.02.017
Raymundo Arroyave, Larry Kaufman, Thomas W. Eagar, Thermodynamic modeling of the ZrO system, Calphad 26, 95-118 (2002). doi:10.1016/s0364-5916(02)00027-5

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}
}