# Cu3Ge: enthalpy of formation

> Enthalpy of formation of Cu3Ge: 3 literature value(s) with sources, pages and quotes, from ORCHID.

HTML: https://data.orchid-project.org/compounds/Cu3Ge.html · Markdown: https://data.orchid-project.org/compounds/Cu3Ge.md

3 accepted literature formation-enthalpy value(s) (experimental 2, model 1).

Systems: [Cu–Ge](https://data.orchid-project.org/systems/CU-GE.html)

## Literature values

Table: Enthalpy of formation of Cu3Ge reported in the literature (3)

| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---:|---|---:|---|---|---|---|---|---|
| -7.66 kJ/mol (basis unstated) | ␩-Cu0.75 Ge0.25 | 780 | experimental |  | [Cu–Ge](https://data.orchid-project.org/systems/CU-GE.html) | [1] Wang 2010; _cites Predel 1971_ [doi](https://doi.org/10.1515/zna-1971-0415) | p. 2; `ORC-VWCKZJ4CRO` | “The enthalpy of formation of intermetallic compound ␩-Cu0.75 Ge0.25 was also obtained by Predel and Stein \[21\] at 780 K, which is -7660 J/mol at 25 at.% Ge.” |
| -7.66 kJ/mol (basis unstated) | ␩-Cu0.75Ge0.25 | 298.15 | experimental |  | [Cu–Ge](https://data.orchid-project.org/systems/CU-GE.html) | [1] Wang 2010; _cites Predel 1971_ [doi](https://doi.org/10.1515/zna-1971-0415) | p. 6; `ORC-XD27I6E7HU.662fc0` | “The enthalpy of formation of solid alloys and intermetallic compounds in the Cu-Ge binary system at 298 K was calculated as presented in Fig. 10. As can be seen, the present calculated values in solid alloys are in excellent agreement with the experimental data measured by Predel and Stein \[21,29\] and Kleppa and King \[31\]. However, the calculated enthalpy of formation of the intermetallic compoun…” |
| -4.245 kJ/mol (basis unstated) | ␩-Cu0.75Ge0.25 | 298.15 | model |  | [Cu–Ge](https://data.orchid-project.org/systems/CU-GE.html) | [1] Wang 2010 | p. 6; `ORC-XD27I6E7HU.df2b9e` | “The enthalpy of formation of solid alloys and intermetallic compounds in the Cu-Ge binary system at 298 K was calculated as presented in Fig. 10. As can be seen, the present calculated values in solid alloys are in excellent agreement with the experimental data measured by Predel and Stein \[21,29\] and Kleppa and King \[31\]. However, the calculated enthalpy of formation of the intermetallic compoun…” |

### 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 Cu3Ge

| Value | Unit | Printed | Reading | Method (class, basis) | Composition | Scatter | Conversion | Effective |
|---:|---|---:|---:|---|---:|---:|---:|---:|
| -7.66 | kJ/mol (basis unstated) |  | 0.005 | 3.5 (unknown, calibrated) |  |  |  | 3.5 |
| -7.66 | kJ/mol (basis unstated) |  | 0.005 | 3.5 (unknown, calibrated) |  |  |  | 3.5 |
| -4.245 | kJ/mol (basis unstated) |  | 5.000e-4 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |

## Sources

1. J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010). [doi:10.1016/j.jallcom.2010.05.077](https://doi.org/10.1016/j.jallcom.2010.05.077)

## 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/).