# Ge system

> Ge system: 27 accepted literature values (crystal structure 19, invariant reaction 4, phase transition 3, activity / EMF / Gibbs energy 1) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

HTML: https://data.orchid-project.org/systems/GE.html · Markdown: https://data.orchid-project.org/systems/GE.md

27 accepted literature values from 8 paper(s) (experimental 12, model 5, DFT 6, unspecified 4); 0 calculated phase diagram(s).

Data: [JSON](https://data.orchid-project.org/literature/systems/GE.json) · [CSV](https://data.orchid-project.org/systems/GE.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#GE) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/GE.html) · [Markdown](https://data.orchid-project.org/systems/GE.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 12 |
| model | 5 |
| DFT | 6 |
| unspecified | 4 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 4 |
| phase transition | 3 |
| activity / EMF / Gibbs energy | 1 |
| crystal structure | 19 |

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the Ge system (4)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1210.15 | congruent melting: L -> (Ge) | L: Ge 1; (Ge): Ge 1 | model | [1] Wang 2008 | Table 4, p. 4, row 18; `ORC-O5MDVKJIHH` |  |
| 1210.15 | congruent melting: L -> (Ge) | L: Ge 1; (Ge): Ge 1 | experimental | [1] Wang 2008; _cites Smith 1989_ | Table 4, p. 4, row 17; `ORC-SQ3L5PWIHF` |  |
| 1209.15 | congruent melting: L ↔ Ge | L: Ge 1 | model | [2] Achgar 2018 | Table 4, p. 7, row 28; `ORC-RCYWAZJD42` |  |
| 1209.15 | congruent melting: L ↔ Ge | L: Ge 1 | experimental | [2] Achgar 2018; _cites Idbenali 2013_ [doi](https://doi.org/10.1007/s10973-012-2271-0) | Table 4, p. 7, row 27; `ORC-U45PUJMGDX` |  |

## Other properties

### Phase transition (3)

Table: Phase transition, Ge system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase transition | 1484.45 K | 1484.45 | congruent melting: L -> Ge; _L: Ge 1; Ge: Ge 1_ | model | [3] Achgar 2017 | Table 2, p. 5, row 44; `ORC-2BJE2GAYNU` |  |
| Phase transition | 1484.45 K | 1484.45 | congruent melting: L -> Ge; _L: Ge 1; Ge: Ge 1_ | experimental | [3] Achgar 2017; _cites Eremenko 1981_ | Table 2, p. 5, row 43; `ORC-4WXYB7TCQW` |  |
| Phase transition | 1484.45 K | 1484.45 | congruent melting: L -> Ge; _L: Ge 1; Ge: Ge 1_ | model | [3] Achgar 2017 | Table 2, p. 5, row 45; `ORC-ZVSALE6OI5` |  |

### Activity / EMF / Gibbs energy (1)

Table: Activity / EMF / Gibbs energy, Ge system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Gibbs energy; _printed: G^ex_ | 0 kJ/mol | 1723 | liquid; _alloy: Ge 1_ | experimental | [4] Bergman 1992 | Table 3, p. 3, row 1; `ORC-MX4X76FL6C.b65724` |  |

### Crystal structure (19)

Table: Crystal structure, Ge system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Lattice a | 4.9908 Å | 0 | (Ba); _(Ba): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 2; `ORC-KJZLBWR2S6.479f3e` |  |
| Lattice a | 5.69 Å | 0 | (Ge); _(Ge): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 26; `ORC-NSJQHMTBJH.2b3ddc` |  |
| Lattice a | 5.013 Å | 298.15 | (Ba); _(Ba): Ge 1_ | experimental | [5] Benhafid 2019; _cites Hirst 1956_ [doi](https://doi.org/10.1021/j150537a011) | Table 2, p. 3, row 1; `ORC-FA7CKYVYIC.8849a7` |  |
| Lattice a | 5.656 Å | 298.15 | (Ge); _(Ge): Ge 1_ | experimental | [5] Benhafid 2019; _cites Straumanis 1952_ [doi](https://doi.org/10.1063/1.1702202) | Table 2, p. 3, row 25; `ORC-EDEEBW47YC.c3ca9f` |  |
| Lattice a | 5.657 Å | 298.15 | (Ge); _alloy: Ge 1_ | experimental | [6] Chen 2022; _cites King 1981_ | Table I, p. 2, row 4; `ORC-N6ECYXPGTF` |  |
| Lattice a | 5.62 Å | 298.15 | (Ge); _(Ge): Ge 1_ | experimental | [7] Cheng 2012 | Table 3, p. 3, row 19; `ORC-OA4JA5FK5B` |  |
| Lattice a | 5.657 Å | 298.15 | (Ge); _(Ge): Ge 1_ | model | [7] Cheng 2012; _cites King 1981_ [doi](https://doi.org/10.1007/bf02868307) | Table 3, p. 3, row 18; `ORC-XZTISEGZWS` |  |
| Lattice a | 4.884 Å | 298.15 | Ge | unspecified | [8] Olesinski 1984 | Table 1, p. 3, row 3; `ORC-F2ADRLYIQM.235914` |  |
| Lattice a | 5.6575 Å | 298.15 | UNKNOWN; _alloy: Ge 1_ | unspecified | [8] Olesinski 1984 | Table 2, p. 3, row 1; `ORC-HACVQMPGDH.dcff40` |  |
| Lattice b | 4.9908 Å | 0 | (Ba); _(Ba): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 2; `ORC-KJZLBWR2S6.4ce079` |  |
| Lattice b | 5.69 Å | 0 | (Ge); _(Ge): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 26; `ORC-NSJQHMTBJH.f1951e` |  |
| Lattice b | 5.013 Å | 298.15 | (Ba); _(Ba): Ge 1_ | experimental | [5] Benhafid 2019; _cites Hirst 1956_ [doi](https://doi.org/10.1021/j150537a011) | Table 2, p. 3, row 1; `ORC-FA7CKYVYIC.7dade3` |  |
| Lattice b | 5.656 Å | 298.15 | (Ge); _(Ge): Ge 1_ | experimental | [5] Benhafid 2019; _cites Straumanis 1952_ [doi](https://doi.org/10.1063/1.1702202) | Table 2, p. 3, row 25; `ORC-EDEEBW47YC.95411b` |  |
| Lattice c | 4.9908 Å | 0 | (Ba); _(Ba): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 2; `ORC-KJZLBWR2S6.3bbc7e` |  |
| Lattice c | 5.69 Å | 0 | (Ge); _(Ge): Ge 1_ | DFT | [5] Benhafid 2019 | Table 2, p. 3, row 26; `ORC-NSJQHMTBJH.817798` |  |
| Lattice c | 5.013 Å | 298.15 | (Ba); _(Ba): Ge 1_ | experimental | [5] Benhafid 2019; _cites Hirst 1956_ [doi](https://doi.org/10.1021/j150537a011) | Table 2, p. 3, row 1; `ORC-FA7CKYVYIC.6db94b` |  |
| Lattice c | 5.656 Å | 298.15 | (Ge); _(Ge): Ge 1_ | experimental | [5] Benhafid 2019; _cites Straumanis 1952_ [doi](https://doi.org/10.1063/1.1702202) | Table 2, p. 3, row 25; `ORC-EDEEBW47YC.0ec0d8` |  |
| Lattice c | 2.692 Å | 298.15 | Ge | unspecified | [8] Olesinski 1984 | Table 1, p. 3, row 3; `ORC-F2ADRLYIQM.581dad` |  |
| lattice unspecified axis | 5.6575 Å | 298.15 | UNKNOWN; _alloy: Ge 1_ | unspecified | [8] Olesinski 1984 | Table 2, p. 3, row 1; `ORC-HACVQMPGDH.0fd5bb` |  |

## Sources

Reporting papers the values were read from (a value cited from another work names that work in its row).

1. C.P. Wang, A.Q. Zheng, X.J. Liu, Thermodynamic assessments of the V–Ge and V–Pt systems, Intermetallics 16, 544-549 (2008). [doi:10.1016/j.intermet.2008.01.002](https://doi.org/10.1016/j.intermet.2008.01.002)
2. Khadija Achgar, Saïd Kardellass, Hassan Azza, Najim Selhaoui, Thermodynamic modeling of the thulium–germanium binary system, J Therm Anal Calorim 131, 2699-2707 (2018). [doi:10.1007/s10973-017-6820-4](https://doi.org/10.1007/s10973-017-6820-4)
3. Khadija Achgar, Saïd Kardellass, Najim Selhaoui, Lahcen Bouirden, Thermodynamic optimization of the Erbium-Germanium binary system, Journal of Alloys and Compounds 724, 1157-1166 (2017). [doi:10.1016/j.jallcom.2017.07.129](https://doi.org/10.1016/j.jallcom.2017.07.129)
4. C. Bergman, R. Chastel, R. Castanet, Thermodynamic investigation on the si-ge binary system by calorimetry and knudsen cell mass spectrometry, JPE 13, 113-118 (1992). [doi:10.1007/bf02667471](https://doi.org/10.1007/bf02667471)
5. R. Benhafid, A. Belgacem Bouzida, Y. Djaballah, A. Candan, A. İyigör, G. Uğur, Thermodynamic Modeling of the Al-Ba and Ba-Ge Systems Supported by First-Principles Calculations, J. Phase Equilib. Diffus. 40, 195-205 (2019). [doi:10.1007/s11669-019-00714-2](https://doi.org/10.1007/s11669-019-00714-2)
6. Shanxiong Chen, Jiong Wang, Shangzhao Yu, Biao Hu, Qing Wu, Yong Du, Thermodynamic Modeling of the Ge-X (X = As, Se, S, P) Systems, J. Electron. Mater. 51, 2114-2130 (2022). [doi:10.1007/s11664-022-09474-1](https://doi.org/10.1007/s11664-022-09474-1)
7. Kaiming Cheng, Biao Hu, Yong Du, Honghui Xu, Qiannan Gao, Thermodynamic modeling of the Ge–Sc system supported by key experiments and first-principles calculation, Calphad 37, 18-24 (2012). [doi:10.1016/j.calphad.2011.12.010](https://doi.org/10.1016/j.calphad.2011.12.010)
8. R. W. Olesinski, G. J. Abbaschian, The Ge−Si (Germanium-Silicon) system, Bulletin of Alloy Phase Diagrams 5, 180-183 (1984). [doi:10.1007/bf02868957](https://doi.org/10.1007/bf02868957)

## 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 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); 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; 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).

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_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/).