# MnO2: enthalpy of formation

> Enthalpy of formation of MnO2: 24 literature value(s) with sources, pages and quotes and DFT values (Materials Project / OQMD), from ORCHID.

HTML: https://data.orchid-project.org/compounds/MnO2.html · Markdown: https://data.orchid-project.org/compounds/MnO2.md

24 accepted literature formation-enthalpy value(s) (experimental 10, model 14); experimental median -174.73 kJ/mol-atom (n = 10); Materials Project -174.236 kJ/mol-atom (mp-aaaabcrz); OQMD -168.93 kJ/mol-atom (oqmd-677684).

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

## Literature values

Table: Enthalpy of formation of MnO2 reported in the literature (24)

| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---:|---|---:|---|---|---|---|---|---|
| -175.007 kJ/mol-atom | MnO2 | 298.15 | experimental | combustion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Ulich 1940_ [doi](https://doi.org/10.1002/srin.194001311) | Table 11, p. 16, row 82; `ORC-6G3UCCQEJ7` |  |
| -175.007 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | experimental | combusion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Siemonsen 1939_ | Table 11, p. 16, row 36; `ORC-6MEP3VUEHP` |  |
| -175.007 kJ/mol-atom | MnO2 | 298.15 | experimental | combustion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Siemonsen 1939_ | Table 11, p. 16, row 81; `ORC-S4PUE2YZBX` |  |
| -175.007 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | experimental | combusion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Ulich 1940_ [doi](https://doi.org/10.1002/srin.194001311) | Table 11, p. 16, row 37; `ORC-VK3JCM3HZI` |  |
| -174.73 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | experimental | combusion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Le 1896_ | Table 11, p. 16, row 34; `ORC-LV2XM5E2UV` |  |
| -174.73 kJ/mol-atom | MnO2 | 298.15 | experimental | combustion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Le 1896_ | Table 11, p. 16, row 79; `ORC-UT4IICGN6R` |  |
| -173.947 kJ/mol-atom | MnO2 | 298.15 | experimental | solution | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Shomate 1943_ [doi](https://doi.org/10.1021/ja01245a016) | Table 11, p. 16, row 83; `ORC-77MUO2SSTH` |  |
| -173.947 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | experimental | solution | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Shomate 1943_ [doi](https://doi.org/10.1021/ja01245a016) | Table 11, p. 16, row 38; `ORC-X6UOHCZYKT` |  |
| -166.913 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | experimental | combusion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Mixter 1910_ [doi](https://doi.org/10.2475/ajs.s4-30.177.193) | Table 11, p. 16, row 35; `ORC-2IE4CVLKVW` |  |
| -166.913 kJ/mol-atom | MnO2 | 298.15 | experimental | combustion | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Mixter 1910_ [doi](https://doi.org/10.2475/ajs.s4-30.177.193) | Table 11, p. 16, row 80; `ORC-JNWIJCB6DJ` |  |
| -174 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Knacke 1991_ | Table 11, p. 16, row 43; `ORC-6X7VMCRTJJ` |  |
| -174 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Knacke 1991_ | Table 11, p. 16, row 88; `ORC-YKGBS4VI2S` |  |
| -173.753 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Rossini 1952_ | Table 11, p. 16, row 39; `ORC-E3OVE2BMWZ` |  |
| -173.753 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Rossini 1952_ | Table 11, p. 16, row 84; `ORC-RPJZ575UDS` |  |
| -173.633 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Kubaschewski 1993_ | Table 11, p. 16, row 44; `ORC-OMTU4J5NWQ` |  |
| -173.633 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Kubaschewski 1993_ | Table 11, p. 16, row 89; `ORC-RYSDFCFCR2` |  |
| -173.613 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Mah 1960_ | Table 11, p. 16, row 86; `ORC-6WRQHNF6DI` |  |
| -173.613 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Mah 1960_ | Table 11, p. 16, row 41; `ORC-7KXME5J3A6` |  |
| -173.493 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003 | Table 11, p. 16, row 90; `ORC-3WAEFRWWHR` |  |
| -173.493 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003 | Table 11, p. 16, row 45; `ORC-7XK3NJVYAK` |  |
| -173.46 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Pankratz 1982_ | Table 11, p. 16, row 42; `ORC-CQWVFKMNOT` |  |
| -173.46 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Pankratz 1982_ | Table 11, p. 16, row 87; `ORC-JNC22JLYEC` |  |
| -173.333 kJ/mol-atom | Pyrolusite (MnO2) | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Brewer 1953_ [doi](https://doi.org/10.1021/cr60161a001) | Table 11, p. 16, row 40; `ORC-QIQPGIMLAL` |  |
| -173.333 kJ/mol-atom | MnO2 | 298.15 | model | assessed | [Mn–O](https://data.orchid-project.org/systems/MN-O.html) | [1] Grundy 2003; _cites Brewer 1953_ [doi](https://doi.org/10.1021/cr60161a001) | Table 11, p. 16, row 85; `ORC-SAKGZUE6OT` |  |

### 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 MnO2

| Value | Unit | Printed | Reading | Method (class, basis) | Composition | Scatter | Conversion | Effective |
|---:|---|---:|---:|---|---:|---:|---:|---:|
| -175.007 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -175.007 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -175.007 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -175.007 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -174.73 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -174.73 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -173.947 | kJ/mol-atom |  | 0.001667 | 3.2 (solution_reaction_calorimetry, calibrated) |  |  |  | 3.2 |
| -173.947 | kJ/mol-atom |  | 0.001667 | 3.2 (solution_reaction_calorimetry, calibrated) |  |  |  | 3.2 |
| -166.913 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -166.913 | kJ/mol-atom |  | 0.001667 | 1 (combustion_calorimetry, cleaned_below_threshold) |  |  |  | 1 |
| -174 | kJ/mol-atom |  | 0.01667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -174 | kJ/mol-atom |  | 0.01667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.753 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.753 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.633 | kJ/mol-atom |  | 0.01667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.633 | kJ/mol-atom |  | 0.01667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.613 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.613 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.493 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.493 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.46 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.46 | kJ/mol-atom |  | 0.001667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.333 | kJ/mol-atom |  | 0.1667 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -173.333 | kJ/mol-atom |  | 0.01667 | 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 MnO2

| Source | Entry | kJ/mol-atom | eV/atom | Space group | E above hull (kJ/mol-atom) | E above hull (eV/atom) | Theoretical |
|---|---|---:|---:|---|---:|---:|---|
| Materials Project | mp-aaaabcrz | -174.236 | -1.80583 | I4/m | -0 | -0 | no |
| OQMD | oqmd-677684 | -168.93 | -1.75084 | I4/m | -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, Assessment of the Mn-O system, JPE 24, 21-39 (2003). [doi:10.1007/s11669-003-0004-6](https://doi.org/10.1007/s11669-003-0004-6)

## 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/).