# Si system

> Si system: 36 accepted literature values (crystal structure 19, formation 8, mixing / partial 3, phase equilibrium 3) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

36 accepted literature values from 16 paper(s) (experimental 10, model 7, DFT 12, unspecified 7); 0 calculated phase diagram(s).

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

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 10 |
| model | 7 |
| DFT | 12 |
| unspecified | 7 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 2 |
| phase equilibrium | 3 |
| formation | 8 |
| mixing / partial | 3 |
| activity / EMF / Gibbs energy | 1 |
| crystal structure | 19 |

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the Si system (2)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1687 | Si1(L) \<=> Si1(dia_A4) | Si1(L): Si 1 | model | [1] Chevalier 1995 | Table 4, p. 9, row 46; `ORC-7XP47HVSRF` |  |
| 1687 | Si1(L) \<=> Si1(dia_A4) | Si1(L): Si 1 | experimental | [1] Chevalier 1995; _cites ref. 2_ | Table 4, p. 9, row 47; `ORC-ZHJME5TUAE` |  |

## Formation enthalpies

Literature values in kJ/mol-atom where the per-atom basis is known. DFT columns: the lowest-energy entry at the same composition (Materials Project 2026.04.13, OQMD v1.8; different energy references, never averaged), from [dft_parity.json](https://data.orchid-project.org/literature/dft_parity.json).

Table: Enthalpies of formation, Si system (8)

| Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote |
|---|---|---:|---:|---|---:|---:|---|---|---|
| Si2Si-γ |  | 148.1 kJ/mol (basis unstated) |  | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 23; `ORC-FN4HDWT3OU.018c64` |  |
| Si2Si-γ |  | 148.1 kJ/mol (basis unstated) | 0 | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 23; `ORC-FN4HDWT3OU.72dfac` |  |
| Si3Si-β |  | 1.88 kJ/mol (basis unstated) | 0 | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 17; `ORC-OCH3VASLIK.8a23e6` |  |
| Si3Si-β |  | 1.88 kJ/mol (basis unstated) |  | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 17; `ORC-OCH3VASLIK.f4b274` |  |
| Si5Si-μ |  | 66.4 kJ/mol (basis unstated) |  | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 6; `ORC-23YDUZX7V5.187576` |  |
| Si5Si-μ |  | 66.4 kJ/mol (basis unstated) | 0 | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 6; `ORC-23YDUZX7V5.9db5e8` |  |
| Si9Si2-α |  | 62.4 kJ/mol (basis unstated) | 0 | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 11; `ORC-EXSHOKKW6H.ac193a` |  |
| Si9Si2-α |  | 62.4 kJ/mol (basis unstated) |  | DFT |  |  | [2] Zhou 2016 | Table I, p. 3, row 11; `ORC-EXSHOKKW6H.f43fac` |  |

## Other properties

### Phase equilibrium (3)

Table: Phase equilibrium, Si system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase composition |  | 900 | Phase 1/dark + Phase 2/white + Phase 1/dark (EDX) + Phase 1/dark (XRD) + Phase 2/white (EDX) + Phase 2/white (XRD); _Phase 1/dark (EDX): Si 0.02; Phase 1/dark (XRD): Si 0.07; Phase 2/white (EDX): Si 0.17; Phase 2/white (XRD): Si 0.3; Phase 1/dark: Si 0.07_ | experimental | [3] Berche 2015 | Table 1, p. 3, row 2; `ORC-DIZS2V63XN` |  |
| Phase composition |  | 900 | Phase 1/dark + Phase 2/white + Phase 1/dark (EDX) + Phase 1/dark (XRD) + Phase 2/white (EDX) + Phase 2/white (XRD); _Phase 1/dark (EDX): Si 0.067; Phase 1/dark (XRD): Si 0.02; Phase 2/white (EDX): Si 0.3; Phase 2/white (XRD): Si 0.29; Phase 1/dark: Si 0.02_ | experimental | [3] Berche 2015 | Table 1, p. 3, row 3; `ORC-LEJFVGZECX` |  |
| Phase composition |  | 900 | Phase 1/dark + Phase 2/white + Phase 1/dark (EDX) + Phase 1/dark (XRD) + Phase 2/white (EDX) + Phase 2/white (XRD); _Phase 1/dark (EDX): Si 0.042; Phase 1/dark (XRD): Si 0.04; Phase 2/white (EDX): Si 0.121; Phase 2/white (XRD): Si 0.16; Phase 1/dark: Si 0.04_ | experimental | [3] Berche 2015 | Table 1, p. 3, row 1; `ORC-U6WWU5JVEB` |  |

### Mixing / partial (3)

Table: Mixing / partial, Si system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Enthalpy of mixing; _printed: ΔH_ | 0 kJ/mol-atom | 1890.15 | liquid; _alloy: Si 1_ | experimental | [4] Gröbner 2004; _cites Sudavtsova 1988_ | Table VIII, p. 11, row 48; `ORC-OFEZUCTYHP.41ee07` |  |
| Enthalpy of mixing; _printed: ΔH_ | 0 kJ/mol-atom | 1923.15 | liquid; _alloy: Si 1_ | model | [4] Gröbner 2004 | Table VIII, p. 11, row 49; `ORC-FGPT7OEDVL.b86bab` |  |
| Enthalpy of mixing; _printed: ΔH_ | 0 kJ/mol-atom | 1923.15 | liquid; _alloy: Si 1_ | experimental | [4] Gröbner 2004; _cites Ryss 1977_ | Table VIII, p. 11, row 47; `ORC-KHVJHSHEFF.3579d9` |  |

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

Table: Activity / EMF / Gibbs energy, Si system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Gibbs energy; _printed: G^ex_ | 0 kJ/mol | 1723 | liquid; _alloy: Si 1_ | experimental | [5] Bergman 1992 | Table 3, p. 3, row 11; `ORC-QAZ74ROOA4.4076aa` |  |

### Crystal structure (19)

Table: Crystal structure, Si system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Lattice a | 5.468 Å | 0 | Diamond_A4 (Si); _alloy: Si 1_ | DFT | [6] Shin 2006 | Table 1, p. 3, row 2; `ORC-H3NBXSM7OX.dc4eb7` |  |
| Lattice a | 5.467 Å |  | Si; _alloy: Si 1_ | DFT | [7] Hao 2012 | Table 1, p. 5, row 4; `ORC-U75BAKDJGL` |  |
| Lattice a | 5.4306 Å | 298.15 | (Si); _(Si): Si 1_ | unspecified | [8] Olesinski 1985 | Table 3, p. 3, row 1; `ORC-33KPDQCY5A` |  |
| Lattice a | 5.43 Å | 298.15 | (Si); _alloy: Si 1_ | model | [9] Long 2018; _cites Okamoto 1990_ [doi](https://doi.org/10.1007/bf03029305) | Table 1, p. 2, row 1; `ORC-4IRZERN3HP` |  |
| Lattice a | 5.4308 Å | 298.15 | (Si); _alloy: Si 1_ | experimental | [8] Olesinski 1985; _cites Bublik 1969_ | Table 3, p. 3, row 3; `ORC-65BM67EK3C` |  |
| Lattice a | 5.4306 Å | 298.15 | (Si); _(Si): Si 1_ | model | [10] Olesinski 1984; _cites King 1982_ | Table 3, p. 3, row 1; `ORC-E2O2XE45T6` |  |
| Lattice a | 5.431 Å | 298.15 | (Si); _alloy: Si 1_ | model | [11] Hu 2013; _cites Massalski 1996_ | Table 3, p. 4, row 3; `ORC-FX7XWD4NCT.09e85b` |  |
| Lattice a | 5.4311 Å | 298.15 | (Si); _alloy: Si 1_ | experimental | [8] Olesinski 1985; _cites Teague 1971_ [doi](https://doi.org/10.1016/0038-1098%2871%2990343-7) | Table 3, p. 3, row 2; `ORC-S53HDBKRHK` |  |
| Lattice a | 5.4306 Å | 298.15 | (Si); _(Si): Si 1_ | unspecified | [12] Olesinski 1985; _cites ref. 1_ | Table 1, p. 2, row 1; `ORC-SDLS6MZF6E` |  |
| Lattice a | 5.4306 Å | 298.15 | (Si); _alloy: Si 1_ | experimental | [13] Qin 2015; _cites King 1981_ | Table 1, p. 2, row 1; `ORC-SNA7IV5XWS` |  |
| Lattice a | 5.43 Å | 298.15 | Si; _alloy: Si 1_ | model | [14] Li 2013; _cites Daams 1991_ | Table 1, p. 2, row 2; `ORC-DFKFZI6PJ6` |  |
| Lattice a | 5.4309 Å | 298.15 | Si; _alloy: Si 1_ | model | [15] Shao 2004; _cites Villars 1991_ | Table 1, p. 2, row 3; `ORC-FKQM3EA6UH` |  |
| Lattice a | 5.431 Å | 298.15 | Si; _alloy: Si 1_ | unspecified | [7] Hao 2012; _cites ref. 28_ | Table 1, p. 5, row 3; `ORC-VBNEWR3QAK` |  |
| Lattice a | 4.686 Å | 298.15 | Si; _alloy: Si 1_ | unspecified | [16] Olesinski 1984 | Table 1, p. 3, row 4; `ORC-ZJSOT32DDW.72f3e6` |  |
| Lattice a | 5.431 Å | 298.15 | UNKNOWN; _alloy: Si 1_ | unspecified | [16] Olesinski 1984 | Table 2, p. 3, row 21; `ORC-U2YKY4VD3X.cdaa61` |  |
| Lattice b | 5.468 Å | 0 | Diamond_A4 (Si); _alloy: Si 1_ | DFT | [6] Shin 2006 | Table 1, p. 3, row 2; `ORC-H3NBXSM7OX.0790a7` |  |
| Lattice c | 5.468 Å | 0 | Diamond_A4 (Si); _alloy: Si 1_ | DFT | [6] Shin 2006 | Table 1, p. 3, row 2; `ORC-H3NBXSM7OX.ac626f` |  |
| Lattice c | 2.585 Å | 298.15 | Si; _alloy: Si 1_ | unspecified | [16] Olesinski 1984 | Table 1, p. 3, row 4; `ORC-ZJSOT32DDW.02769f` |  |
| lattice unspecified axis | 5.431 Å | 298.15 | UNKNOWN; _alloy: Si 1_ | unspecified | [16] Olesinski 1984 | Table 2, p. 3, row 21; `ORC-U2YKY4VD3X.569221` |  |

## Sources

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

1. Pierre-Yves Chevalier, E. Fischer, A. Rivet, A thermodynamic evaluation of the Mn-Si system, Calphad 19, 57-68 (1995). [doi:10.1016/0364-5916(95)00007-2](https://doi.org/10.1016/0364-5916%2895%2900007-2)
2. S. H. Zhou, Y. Huo, Ralph E. Napolitano, Phase Stability for the Pd-Si System: First-Principles, Experiments, and Solution-Based Modeling, Metall Mater Trans A 47, 194-208 (2016). [doi:10.1007/s11661-015-3206-8](https://doi.org/10.1007/s11661-015-3206-8)
3. Alexandre Berche, Elodie Théron-Ruiz, Jean-Claude Tédenac, Philippe Jund, Thermodynamic study of the Ge–Mn–Si system, Journal of Alloys and Compounds 632, 10-16 (2015). [doi:10.1016/j.jallcom.2015.01.072](https://doi.org/10.1016/j.jallcom.2015.01.072)
4. Joachim Gröbner, Djordje Mirković, Rainer Schmid-Fetzer, Thermodynamic aspects of the constitution, grain refining, and solidification enthalpies of Al-Ce-Si alloys, Metall Mater Trans A 35, 3349-3362 (2004). [doi:10.1007/s11661-004-0172-y](https://doi.org/10.1007/s11661-004-0172-y)
5. 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)
6. Dongwon Shin, Raymundo Arróyave, Zi-Kui Liu, Thermodynamic modeling of the Hf–Si–O system, Calphad 30, 375-386 (2006). [doi:10.1016/j.calphad.2006.08.006](https://doi.org/10.1016/j.calphad.2006.08.006)
7. D. Hao, M. Bu, Y. Wang, Y. Tang, Q. Gao, M. Wang et al., Thermodynamic modeling of the Na-X (X = Si, Ag, Cu, Cr) systems, J min metall B Metall 48, 273-282 (2012). [doi:10.2298/jmmb120113024h](https://doi.org/10.2298/jmmb120113024h)
8. R. W. Olesinski, G. J. Abbaschian, The Sb-Si (Antimony-Silicon) system, Bulletin of Alloy Phase Diagrams 6, 445-448 (1985). [doi:10.1007/bf02869508](https://doi.org/10.1007/bf02869508)
9. Zhaohui Long, Xiaorong Dai, Zhi Li, Fucheng Yin, Zhanpeng Jin, Experimental investigation and thermodynamic description of the Li–Si–Mn ternary system, Journal of Alloys and Compounds 768, 686-696 (2018). [doi:10.1016/j.jallcom.2018.07.211](https://doi.org/10.1016/j.jallcom.2018.07.211)
10. R. W. Olesinski, G. J. Abbaschian, The Pb−Si (Lead−Silicon) system, Bulletin of Alloy Phase Diagrams 5, 271-273 (1984). [doi:10.1007/bf02868551](https://doi.org/10.1007/bf02868551)
11. Biao Hu, Wei-Wei Zhang, Yingbiao Peng, Yong Du, Shuhong Liu, Yuelan Zhang, Thermodynamic reassessment of the Al–Cr–Si system with the refined description of the Al–Cr system, Thermochimica Acta 561, 77-90 (2013). [doi:10.1016/j.tca.2013.03.033](https://doi.org/10.1016/j.tca.2013.03.033)
12. R. W. Olesinski, N. Kanani, G. J. Abbaschian, The In−Si (Indium-Silicon) system, Bulletin of Alloy Phase Diagrams 6, 128-130 (1985). [doi:10.1007/bf02869223](https://doi.org/10.1007/bf02869223)
13. Aning Qin, Dandan Liu, Chong Chen, Shuhong Liu, Yong Du, Man Wang et al., Heat contents of Sc5Si3 and ScSi intermetallics and thermodynamic modeling of the Sc–Si system, J Therm Anal Calorim 119, 1315-1321 (2015). [doi:10.1007/s10973-014-4216-2](https://doi.org/10.1007/s10973-014-4216-2)
14. Yan Li, Changrong Li, Zhenmin Du, Cuiping Guo, Thermodynamic optimization of the Nb–Si–W ternary system, Calphad 43, 112-123 (2013). [doi:10.1016/j.calphad.2013.04.004](https://doi.org/10.1016/j.calphad.2013.04.004)
15. G. Shao, Thermodynamic assessment of the Nb–Si–Al system, Intermetallics 12, 655-664 (2004). [doi:10.1016/j.intermet.2004.03.011](https://doi.org/10.1016/j.intermet.2004.03.011)
16. 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/).