Fe2U: enthalpy of formation

14 accepted literature formation-enthalpy value(s) (experimental 3, model 11); experimental median -14.01 kJ/mol-atom (n = 3); Materials Project -9.82 kJ/mol-atom (mp-aaaabfdq); OQMD -8.017 kJ/mol-atom (oqmd-19298).

Systems: Fe–U

Literature values

Enthalpy of formation of Fe2U reported in the literature (14)
Value	Phase as printed	T (K)	Class	Method	System	Source	Location
-16.3 kJ/mol-atom ± 0.6	Fe2U	298.15	experimental	High temperature solution calorimetry	Fe–U	[1] Chatain 2003 cites Labroche 2000	Table 3, p. 3, row 3 report
-14.01 kJ/mol-atom ± 1.8	Fe2U	298.15	experimental	High temperature solution calorimetry	Fe–U	[1] Chatain 2003 cites Antony 1996 doi	Table 3, p. 3, row 2 report
-10.74 kJ/mol-atom ± 0.42	Fe2U	298.15	experimental	Acid solution calorimetry	Fe–U	[1] Chatain 2003 cites Akhachinskiy 1962	Table 3, p. 3, row 1 report
-34.112 kJ/mol (basis unstated)	Fe2U	298.15	model		Fe–U	[1] Chatain 2003	Table 7, p. 8, row 14 report
-30.08 kJ/mol (basis unstated)	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003 cites Kurata 2003	Table 7, p. 8, row 15 report
-25.314 kJ/mol (basis unstated)	Fe2U	298.15	model		Fe–U	[1] Chatain 2003 cites Okamoto 1993 doi	Table 7, p. 8, row 13 report
-23.54 kJ/mol (basis unstated) ± 0.45	Fe2U	298.15	model		Fe–U	[1] Chatain 2003 cites Kanno 1974	Table 7, p. 8, row 10 report
-20.6 kJ/mol (basis unstated)	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003 cites Campbell 1977 doi	Table 7, p. 8, row 8 report
-16.922 kJ/mol (basis unstated)	Fe2U	298.15	model		Fe–U	[1] Chatain 2003	Table 7, p. 8, row 11 report
-16.3 kJ/mol (basis unstated) ± 0.6	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003 cites Labroche 2000	Table 7, p. 8, row 5 report
-15.886 kJ/mol (basis unstated)	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003	Table 7, p. 8, row 6 report
-15.025 kJ/mol (basis unstated)	Fe2U	298.15	model		Fe–U	[1] Chatain 2003 cites Gardie 1992 doi	Table 7, p. 8, row 12 report
-14.01 kJ/mol (basis unstated) ± 1.8	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003 cites Antony 1996 doi	Table 7, p. 8, row 7 report
-10.739 kJ/mol (basis unstated) ± 0.42	Fe0.66U0.33	298.15	model		Fe–U	[1] Chatain 2003 cites Akhachinskiy 1962	Table 7, p. 8, row 9 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 Fe2U
Value	Unit	Printed	Reading	Method (class, basis)	Effective
-16.3	kJ/mol-atom	0.6	0.05	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-14.01	kJ/mol-atom	1.8	0.005	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-10.74	kJ/mol-atom	0.42	0.005	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-34.112	kJ/mol (basis unstated)		5.000e-5	11.7 (model_calculated, calibrated)	11.7
-30.08	kJ/mol (basis unstated)		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-25.314	kJ/mol (basis unstated)		5.000e-5	11.7 (model_calculated, calibrated)	11.7
-23.54	kJ/mol (basis unstated)	0.45	5.000e-5	11.7 (model_calculated, calibrated)	11.7
-20.6	kJ/mol (basis unstated)		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-16.922	kJ/mol (basis unstated)		5.000e-5	11.7 (model_calculated, calibrated)	11.7
-16.3	kJ/mol (basis unstated)	0.6	5.000e-4	3.9 (model_calculated, calibrated)	3.9
-15.886	kJ/mol (basis unstated)		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-15.025	kJ/mol (basis unstated)		5.000e-5	11.7 (model_calculated, calibrated)	11.7
-14.01	kJ/mol (basis unstated)	1.8	5.000e-4	3.9 (model_calculated, calibrated)	3.9
-10.739	kJ/mol (basis unstated)	0.42	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 Fe2U
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaabfdq	-9.82	-0.101774	Fd-3m	0	0	no
OQMD	oqmd-19298	-8.017	-0.08309	Fd-3m	0.7002	0.0073	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

S. Chatain, C. Guéneau, D. Labroche, O. Dugne, J. Rogez, Thermodynamic assessment of the Fe-U binary system, JPE 24, 122-131 (2003). doi:10.1361/105497103770330730

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}
}