# B–Ba system

> B–Ba system: 8 accepted literature values (formation 6, invariant reaction 2) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

8 accepted literature values from 1 paper(s) (model 8); 0 calculated phase diagram(s).

Data: [JSON](https://data.orchid-project.org/literature/systems/B-BA.json) · [CSV](https://data.orchid-project.org/systems/B-BA.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#B-BA) · [phases (7)](https://data.orchid-project.org/phases/pages/B-BA.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/B-BA.html) · [Markdown](https://data.orchid-project.org/systems/B-BA.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| model | 8 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 2 |
| formation | 6 |

Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/B/B-BA.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/B/B-BA.json)

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the B–Ba system (2)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1388 | BaB6 + β(B) = α(B) | BaB6: Ba 0.143; β(B): Ba 0; α(B): Ba 0 | model | [1] Shang 2007 | Table 4, p. 5, row 19; `ORC-FUPWUCOV3V` |  |
| 1000 | liq1 = BaB6 + bcc(Ba) | liq1: Ba 1; BaB6: Ba 0.143; bcc(Ba): Ba 1 | model | [1] Shang 2007 | Table 4, p. 5, row 20; `ORC-DMMVQVHRRF` |  |

## 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, B–Ba system (3)

| Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote |
|---|---|---:|---:|---|---:|---:|---|---|---|
| BaB6 | [BaB6](https://data.orchid-project.org/compounds/BaB6.html) | -40.8625 kJ/mol-atom | 298.15 | model | -39.556 (mp-aaaaabks) | -39.486 (oqmd-646731) | [1] Shang 2007 | Table 3, p. 3, row 9; `ORC-F6FRHUH4YQ.5c6e86` |  |
| BaB6 | [BaB6](https://data.orchid-project.org/compounds/BaB6.html) | -40.8376 kJ/mol-atom | 298.15 | model | -39.556 (mp-aaaaabks) | -39.486 (oqmd-646731) | [1] Shang 2007 | Table 3, p. 3, row 11; `ORC-4FLGV5BABI.d5bcaa` |  |
| BaB6 | [BaB6](https://data.orchid-project.org/compounds/BaB6.html) | -40.2307 kJ/mol-atom | 298.15 | model | -39.556 (mp-aaaaabks) | -39.486 (oqmd-646731) | [1] Shang 2007 | Table 3, p. 3, row 12; `ORC-24JL5Z7OLO.ead560` |  |

## Other properties

### Formation (3)

Table: Formation, B–Ba system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Entropy of formation; _printed: ΔfS298_ | -0.168946 J/mol-atom/K | 298.15 | BaB6; _alloy: Ba 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 12; `ORC-24JL5Z7OLO.b84fdb` |  |
| Entropy of formation; _printed: ΔfS298_ | -1.68914 J/mol-atom/K | 298.15 | BaB6; _alloy: Ba 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 11; `ORC-4FLGV5BABI.f7b7ce` |  |
| Entropy of formation; _printed: ΔfS298_ | -1.68956 J/mol-atom/K | 298.15 | BaB6; _alloy: Ba 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 9; `ORC-F6FRHUH4YQ.30389e` |  |

## Sources

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

1. Shunli Shang, Tao Wang, Zi-Kui Liu, Thermodynamic modelling of the B–Ca, B–Sr and B–Ba systems, Calphad 31, 286-291 (2007). [doi:10.1016/j.calphad.2006.11.005](https://doi.org/10.1016/j.calphad.2006.11.005)

## 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-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD) (version 2026.10), Zenodo (2026). https://doi.org/10.5281/zenodo.23735891
- 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); 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_hulls_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD)}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735891},
  url       = {https://doi.org/10.5281/zenodo.23735891}
}

@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/).
