# Cr5Ge3: enthalpy of formation

> Enthalpy of formation of Cr5Ge3: 4 literature value(s) with sources, pages and quotes and DFT values (Materials Project / OQMD), from ORCHID.

HTML: https://data.orchid-project.org/compounds/Cr5Ge3.html · Markdown: https://data.orchid-project.org/compounds/Cr5Ge3.md

4 accepted literature formation-enthalpy value(s) (experimental 2, model 2); experimental median -14 kJ/mol-atom (n = 2); Materials Project 1.856 kJ/mol-atom (mp-aaabgisq); OQMD 1.106 kJ/mol-atom (oqmd-13726).

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

## Literature values

Table: Enthalpy of formation of Cr5Ge3 reported in the literature (4)

| Value | Phase as printed | T (K) | Class | Method | System | Source | Location | Quote |
|---:|---|---:|---|---|---|---|---|---|
| -15.7 kJ/mol-atom ± 1 | αCr5Ge3 | 298.15 | experimental | Direct calorimetry | [Cr–Ge](https://data.orchid-project.org/systems/CR-GE.html) | [1] Liu 2010; _cites Kleppa 1990_ | Table 4, p. 7, row 5; `ORC-VYDTBVQGR6.7e076a` |  |
| -12.3 kJ/mol-atom ± 2.5 | αCr5Ge3 | 298.15 | experimental | Knudsen effusion mass spectrometry | [Cr–Ge](https://data.orchid-project.org/systems/CR-GE.html) | [1] Liu 2010; _cites Zarembo 2001_ [doi](https://doi.org/10.1016/s0925-8388%2801%2901551-1) | Table 4, p. 7, row 4; `ORC-6HTTW5327W.8f41bd` |  |
| -16.3 kJ/mol-atom | αCr5Ge3 | 298.15 | model | Thermodynamic optimization | [Cr–Ge](https://data.orchid-project.org/systems/CR-GE.html) | [1] Liu 2010 | Table 4, p. 7, row 6; `ORC-P3R7LHZLX4.17f577` |  |
| -12.3 unspecified ± 2.5 | Cr5Ge3 | 298.15 | model |  | [Cr–Ge](https://data.orchid-project.org/systems/CR-GE.html) | [1] Liu 2010; _cites Zarembo 2001_ [doi](https://doi.org/10.1016/s0925-8388%2801%2901551-1) | p. 3; `ORC-FIZHRAX3MJ.2ba266` | “The reported standard enthalpies of formation at 298 K are -19.3 ± 2.5 kJ/mol atom for Cr0.75 Ge0.25 (Cr3 Ge) and -12.3 ± 2.5 kJ/mol-atom for Cr0.63 Ge0.37 (Cr5 Ge3 ).” |

### 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 Cr5Ge3

| Value | Unit | Printed | Reading | Method (class, basis) | Composition | Scatter | Conversion | Effective |
|---:|---|---:|---:|---|---:|---:|---:|---:|
| -15.7 | kJ/mol-atom | 1 | 0.05 | 3.2 (solution_reaction_calorimetry, calibrated) |  |  |  | 3.2 |
| -12.3 | kJ/mol-atom | 2.5 | 0.05 | 4.2 (kems_vapour, calibrated) |  |  |  | 4.2 |
| -16.3 | kJ/mol-atom |  | 0.05 | 3.9 (model_calculated, calibrated) |  |  |  | 3.9 |
| -12.3 | unspecified | 2.5 | 0.05 | unit 'unspecified' not convertible to kJ/mol-atom |  |  |  | 2.5 |

## 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.

Table: DFT formation energy of Cr5Ge3

| Source | Entry | kJ/mol-atom | eV/atom | Space group | E above hull (kJ/mol-atom) | E above hull (eV/atom) | Theoretical |
|---|---|---:|---:|---|---:|---:|---|
| Materials Project | mp-aaabgisq | 1.856 | 0.019241 | I4/mcm | 10.8566 | 0.1125 | no |
| OQMD | oqmd-13726 | 1.106 | 0.011464 | I4/mcm | 11.716 | 0.1214 | 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. Y.Q. Liu, Y. Du, Thermodynamic description of the Cr–Ge system, Calphad 34, 26-35 (2010). [doi:10.1016/j.calphad.2009.11.001](https://doi.org/10.1016/j.calphad.2009.11.001)

## 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/).
