# Er–H system

> Er–H system: 15 accepted literature values (crystal structure 15) and 1 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

15 accepted literature values from 1 paper(s) (experimental 15); 1 calculated phase diagram(s).

Data: [JSON](https://data.orchid-project.org/literature/systems/ER-H.json) · [CSV](https://data.orchid-project.org/systems/ER-H.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#ER-H) · [interactive phase diagram](https://orchid-project.org/phase-diagrams/#ER-H/ErH-13Mas.json) · [phases (5)](https://data.orchid-project.org/phases/pages/ER-H.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/ER-H.html) · [Markdown](https://data.orchid-project.org/systems/ER-H.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 15 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| crystal structure | 15 |

## Calculated phase diagrams

Binary phase diagrams calculated with pycalphad 0.11.2 from the SGTE binary collection (Hallstedt 2025, CC BY 4.0). Evidence class: model.

Table: Assessments with a calculated phase diagram

| TDB file | Assessment | SHA-256 | Links |
|---|---|---|---|
| ErH-13Mas.tdb | A. Mascaro, C. Toffolon-Masclet, C. Raepsaet, J.-M. Joubert, Calphad, 41, 50-59(2013). [doi:10.1016/j.calphad.2013.01.004](https://doi.org/10.1016/j.calphad.2013.01.004) | `f6f27fb09e27c3aae23f3a8b02f33cceabaab15d13f779ca07628fdc65061203` | [viewer](https://orchid-project.org/phase-diagrams/#ER-H/ErH-13Mas.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/ErH-13Mas.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/ErH-13Mas.json) |

Table: Calculated three-phase invariants (model, mole fraction of the second component)

| TDB file | T (K) | Phases at the invariant |
|---|---:|---|
| ErH-13Mas.tdb | 2047.56 | LIQUID (x(H) 0.00496) + HCP_A3 (x(H) 0.13032) + GAS (x(H) 1) |
| ErH-13Mas.tdb | 1494.6 | HCP_A3 (x(H) 0.39121) + FCC_A1 (x(H) 0.44743) + GAS (x(H) 1) |
| ErH-13Mas.tdb | 654.24 | FCC_A1 (x(H) 0.70158) + HCP_A3 (x(H) 0.7495) + GAS (x(H) 1) |

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

## Other properties

### Crystal structure (15)

Table: Crystal structure, Er–H system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Lattice a | 5.123 Å |  | β-ErH2; _alloy: H 0.666667_ | experimental | [1] Mascaro 2013; _cites Pebler 1962_ [doi](https://doi.org/10.1021/j100807a033) | Table 1, p. 2, row 2; `ORC-OMHQS477Y6` |  |
| Lattice a | 3.56 Å | 298.15 | α\_Er; _α\_Er: Er 0.839, H 0.161; αEr: Er 0.839, H 0.161_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 1; `ORC-4GQDV7O3F7.990cef` |  |
| Lattice a | 3.566 Å | 298.15 | α\_Er; _α\_Er: Er 0.6, H 0.4; αEr: Er 0.6, H 0.4_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 5; `ORC-D6AHHLF6DN.62b6eb` |  |
| Lattice a | 5.119 Å | 298.15 | β-ErH2; _β-ErH2: Er 0.3, H 0.7_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 2; `ORC-EXSVPQMEWD` |  |
| Lattice a | 5.124 Å | 298.15 | β-ErH2; _β-ErH2: Er 0.349, H 0.651_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 7; `ORC-O3CX7AAAMU` |  |
| Lattice a | 5.122 Å | 298.15 | β-ErH2; _β-ErH2: Er 0.39, H 0.61_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 8; `ORC-QG3KV6SEXI` |  |
| Lattice a | 5.125 Å | 298.15 | β-ErH2; _β-ErH2: Er 0.373, H 0.627_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 6; `ORC-ZFRFQWTFSA` |  |
| Lattice a | 6.264 Å | 298.15 | γ-ErH3; _γ-ErH3: Er 0.275, H 0.725_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 10; `ORC-6USEOM7IC7.b1c357` |  |
| Lattice a | 6.272 Å | 298.15 | γ-ErH3; _alloy: H 0.75_ | experimental | [1] Mascaro 2013; _cites Pebler 1962_ [doi](https://doi.org/10.1021/j100807a033) | Table 1, p. 2, row 3; `ORC-FILN3BMDFM.e5ecaf` |  |
| Lattice a | 6.268 Å | 298.15 | γ-ErH3; _γ-ErH3: Er 0.313, H 0.687_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 9; `ORC-ZCXDOF23HK.4bcc8a` |  |
| Lattice c | 5.581 Å | 298.15 | α\_Er; _α\_Er: Er 0.839, H 0.161; αEr: Er 0.839, H 0.161_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 1; `ORC-4GQDV7O3F7.378ec9` |  |
| Lattice c | 5.602 Å | 298.15 | α\_Er; _α\_Er: Er 0.6, H 0.4; αEr: Er 0.6, H 0.4_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 5; `ORC-D6AHHLF6DN.53ce21` |  |
| Lattice c | 6.52 Å | 298.15 | γ-ErH3; _γ-ErH3: Er 0.275, H 0.725_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 10; `ORC-6USEOM7IC7.c9f5e9` |  |
| Lattice c | 6.526 Å | 298.15 | γ-ErH3; _alloy: H 0.75_ | experimental | [1] Mascaro 2013; _cites Pebler 1962_ [doi](https://doi.org/10.1021/j100807a033) | Table 1, p. 2, row 3; `ORC-FILN3BMDFM.f958af` |  |
| Lattice c | 6.525 Å | 298.15 | γ-ErH3; _γ-ErH3: Er 0.313, H 0.687_ | experimental | [1] Mascaro 2013 | Table 3, p. 4, row 9; `ORC-ZCXDOF23HK.4f34b0` |  |

## Sources

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

1. Aurore Mascaro, Caroline Toffolon-Masclet, Caroline Raepsaet, Jean-Marc Joubert, Experimental study and thermodynamic assessment of the erbium–hydrogen binary system, Calphad 41, 50-59 (2013). [doi:10.1016/j.calphad.2013.01.004](https://doi.org/10.1016/j.calphad.2013.01.004)

## 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-Diagrams: calculated binary phase diagrams (version 2026.10), Zenodo (2026). https://doi.org/10.5281/zenodo.23735859
- 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); 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_phase_diagrams_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Diagrams: calculated binary phase diagrams}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735859},
  url       = {https://doi.org/10.5281/zenodo.23735859}
}

@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/).