# La2O3: enthalpy of formation

> Enthalpy of formation of La2O3: 17 literature value(s) with sources, pages and quotes and DFT values (Materials Project / OQMD), from ORCHID.

HTML: https://data.orchid-project.org/compounds/La2O3.html · Markdown: https://data.orchid-project.org/compounds/La2O3.md

17 accepted literature formation-enthalpy value(s) (experimental 14, model 3); Materials Project -373.797 kJ/mol-atom (mp-aaaaadke); OQMD -358.204 kJ/mol-atom (oqmd-30652).

Systems: [La–O](https://data.orchid-project.org/systems/LA-O.html)

## Literature values

Table: Enthalpy of formation of La2O3 reported in the literature (17)

| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---:|---|---:|---|---|---|---|---|---|
| -2255.2 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Roth 1940_ | Table 3, p. 3, row 11; `ORC-7HVF4JYGKC` |  |
| -2255.2 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Roth 1940_ | Table 3, p. 3, row 3; `ORC-YFLPG2T5CJ` |  |
| -1907.4 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Moose 1932_ | Table 3, p. 3, row 10; `ORC-VTONN5KR2B` |  |
| -1907.4 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Moose 1932_ | Table 3, p. 3, row 2; `ORC-WODDK3PHVQ` |  |
| -1866.1 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Von 1959_ | Table 3, p. 3, row 5; `ORC-N2BINSDHMC` |  |
| -1866.1 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Von 1959_ | Table 3, p. 3, row 13; `ORC-SNQD26D234` |  |
| -1862.1 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Muthmann 1904_ [doi](https://doi.org/10.1002/jlac.19043310102) | Table 3, p. 3, row 1; `ORC-MZVN67SSDB` |  |
| -1862.1 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Muthmann 1904_ [doi](https://doi.org/10.1002/jlac.19043310102) | Table 3, p. 3, row 9; `ORC-YGURYXCQZ3` |  |
| -1797.9 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Gvelesiani 1967_ | Table 3, p. 3, row 15; `ORC-5IIOJL5L26` |  |
| -1797.9 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Gvelesiani 1967_ | Table 3, p. 3, row 7; `ORC-O42ENWTUDL` |  |
| -1794.5 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Fitzgibbon 1965_ [doi](https://doi.org/10.1021/j100891a504) | Table 3, p. 3, row 14; `ORC-5GOJNYDWQX` |  |
| -1794.5 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Solution calorimetry, Born-Haber cycle | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Fitzgibbon 1965_ [doi](https://doi.org/10.1021/j100891a504) | Table 3, p. 3, row 6; `ORC-NJY6NALODN` |  |
| -1793.3 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Huber 1953_ [doi](https://doi.org/10.1021/ja01110a511) | Table 3, p. 3, row 12; `ORC-DMGNH64DQO` |  |
| -1793.3 kJ/mol (basis unstated) | La2O3 | 298.15 | experimental | Combustion calorimetry | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001; _cites Huber 1953_ [doi](https://doi.org/10.1021/ja01110a511) | Table 3, p. 3, row 4; `ORC-LZHJ3DOIB7` |  |
| -1795.5 kJ/mol (basis unstated) | La2O3 | 298.15 | model | Optimized | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001 | Table 3, p. 3, row 8; `ORC-TJJQJSMBNO` |  |
| -1795.5 kJ/mol (basis unstated) | La2O3 | 298.15 | model | Optimized | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [1] Grundy 2001 | Table 3, p. 3, row 16; `ORC-WDJW24J6FZ` |  |
| -358.32 kJ/mol-atom | A-La2O3 | 298.15 | model |  | [La–O](https://data.orchid-project.org/systems/LA-O.html) | [2] ZINKEVICH 2007 | Table 6.1, p. 24, row 13; `ORC-R5Z7F2ZFHA.25c306` |  |

### Uncertainty budget

Components kept separate, in the value's unit (literature [SCHEMA.md](https://data.orchid-project.org/literature/SCHEMA.md), [UNCERTAINTY_CALIBRATION.md](https://data.orchid-project.org/literature/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.

Table: Uncertainty budget of the literature values of La2O3

| Value | Unit | Printed | Reading | Method (class, basis) | Composition | Scatter | Conversion | Effective |
|---:|---|---:|---:|---|---:|---:|---:|---:|
| -2255.2 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -2255.2 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1907.4 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1907.4 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1866.1 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1866.1 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1862.1 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1862.1 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1797.9 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1797.9 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1794.5 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1794.5 | kJ/mol (basis unstated) |  | 0.05 | 16 (solution_reaction_calorimetry, calibrated) |  |  |  | 16 |
| -1793.3 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1793.3 | kJ/mol (basis unstated) |  | 0.05 | 5 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 5 |
| -1795.5 | kJ/mol (basis unstated) |  | 0.05 | 19.5 (model_calculated, calibrated) |  |  |  | 19.5 |
| -1795.5 | kJ/mol (basis unstated) |  | 0.05 | 19.5 (model_calculated, calibrated) |  |  |  | 19.5 |
| -358.32 | kJ/mol-atom |  | 1.000e-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.

Table: DFT formation energy of La2O3

| Source | Entry | kJ/mol-atom | eV/atom | Space group | E above hull (kJ/mol-atom) | E above hull (eV/atom) | Theoretical |
|---|---|---:|---:|---|---:|---:|---|
| Materials Project | mp-aaaaadke | -373.797 | -3.87414 | Ia-3 | 0 | 0 | no |
| OQMD | oqmd-30652 | -358.204 | -3.71254 | Ia-3 | 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](https://doi.org/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](https://doi.org/10.1007/s11837-013-0755-4) (CC BY 4.0); 

## Sources

1. A. Nicholas Grundy, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic assessment of the lanthanum-oxygen system, JPE 22, 105-113 (2001). [doi:10.1361/105497101770338950](https://doi.org/10.1361/105497101770338950)
2. M ZINKEVICH, Thermodynamics of rare earth sesquioxides, Progress in Materials Science 52, 597-647 (2007). [doi:10.1016/j.pmatsci.2006.09.002](https://doi.org/10.1016/j.pmatsci.2006.09.002)

## 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). https://doi.org/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). https://doi.org/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). https://doi.org/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.

```bibtex
@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}
}
```

---

Derived data CC BY 4.0 ([licence](https://creativecommons.org/licenses/by/4.0/)): cite ORCHID ([CITATION.cff](https://data.orchid-project.org/CITATION.cff)) and the original sources. Quotes are short excerpts kept so that each value can be checked; they remain under the publishers' copyright and are not relicensed. Source papers, page images and full text are not redistributed. Field reference: [SCHEMA.md](https://data.orchid-project.org/literature/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt). Found an error? The report link of a value (Markdown: its id, ORC-..., in the Location column) opens a pre-filled GitHub issue, https://github.com/orchid-calphad/orchid-data/issues/new?template=report-value-error.yml&record_id=\<id>, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).