# Pu–U system

> Pu–U system: 6 accepted literature values (heat capacity / entropy / enthalpy 6) and 4 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

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

6 accepted literature values from 1 paper(s) (experimental 3, model 3); 4 calculated phase diagram(s). 2 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: [JSON](https://data.orchid-project.org/literature/systems/PU-U.json) · [CSV](https://data.orchid-project.org/systems/PU-U.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#PU-U) · [interactive phase diagram](https://orchid-project.org/phase-diagrams/#PU-U/PuU-10Kur.json) · [phases (12)](https://data.orchid-project.org/phases/pages/PU-U.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/PU-U.html) · [Markdown](https://data.orchid-project.org/systems/PU-U.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 3 |
| model | 3 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| heat capacity / entropy / enthalpy | 6 |

## 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 |
|---|---|---|---|
| PuU-10Kur.tdb | M. Kurata, IOP Conf. Ser.: Mater. Sci. Eng., 9, 012022(2010). | `ae973a5f25fff5bd033b8dff9e46729f02bd72f047d46f5f8f4ffacd93b5b5fa` | [viewer](https://orchid-project.org/phase-diagrams/#PU-U/PuU-10Kur.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/PuU-10Kur.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/PuU-10Kur.json) |
| PuU-15Per.tdb | A. Perron, P.E.A. Turchi, A. Landa, P. Soderlind, B. Ravat, B. Oudot, F. Delaunay, J. Nucl. Mater., 458, 425-41(2015). [doi:10.1016/j.jnucmat.2014.12.101](https://doi.org/10.1016/j.jnucmat.2014.12.101) | `b2766bcd4fb5f7f589f31d56f77d51147d22fdb177fb21b4a7215f3f94bd0ad5` | [viewer](https://orchid-project.org/phase-diagrams/#PU-U/PuU-15Per.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/PuU-15Per.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/PuU-15Per.json) |
| PuU-23Fou.tdb | P. Fouquet-Metivier, P.M. Martin, D. Manara, K. Dardenne, J. Rothe, P.C.M. Fossati, C. Gueneau, Calphad, 80, 102523(2023). [doi:10.1016/j.calphad.2022.102523](https://doi.org/10.1016/j.calphad.2022.102523) | `b15fc83561b2855604b98968affcc9bb7e3b7aa5cb93f3c392bdf75fd3ca7897` | [viewer](https://orchid-project.org/phase-diagrams/#PU-U/PuU-23Fou.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/PuU-23Fou.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/PuU-23Fou.json) |
| PuU-99Kur.tdb | M. Kurata, Calphad, 23, 305-37(1999). [doi:10.1016/S0364-5916(00)00004-3](https://doi.org/10.1016/S0364-5916%2800%2900004-3) | `f7466d1c08e571115d2e08747bda9b6f11c2f8c9d1d955556c18109bf13bf340` | [viewer](https://orchid-project.org/phase-diagrams/#PU-U/PuU-99Kur.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/PuU-99Kur.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/PuU-99Kur.json) |

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

| TDB file | T (K) | Phases at the invariant |
|---|---:|---|
| PuU-10Kur.tdb | 975.28 | BCC_A2 (x(U) 0.67291) + PUU_ETA (x(U) 0.72933) + TETRAGONAL_U (x(U) 0.78749) |
| PuU-10Kur.tdb | 866.19 | PUU_ETA (x(U) 0.73466) + PUU_ZETA (x(U) 0.7426) + TETRAGONAL_U (x(U) 0.79617) |
| PuU-10Kur.tdb | 841.05 | PUU_ZETA (x(U) 0.76791) + TETRAGONAL_U (x(U) 0.82535) + ORTHORHOMBIC_A20 (x(U) 0.87179) |
| PuU-10Kur.tdb | 728.05 | TETRAGONAL_A6 (x(U) 0.01458) + BCC_A2 (x(U) 0.02485) + PUU_ETA (x(U) 0.04422) |
| PuU-10Kur.tdb | 713.15 | FCC_A1 (x(U) 0.01259) + TETRAGONAL_A6 (x(U) 0.01307) + PUU_ETA (x(U) 0.04104) |
| PuU-10Kur.tdb | 593.43 | FCC_A1 (x(U) 0.00284) + GAMMA_PU (x(U) 0.00294) + PUU_ETA (x(U) 0.01304) |
| PuU-10Kur.tdb | 485.97 | BETA_PU (x(U) 0.00265) + GAMMA_PU (x(U) 0.00312) + PUU_ETA (x(U) 0.01544) |
| PuU-10Kur.tdb | 450.47 | BETA_PU (x(U) 0.00449) + PUU_ETA (x(U) 0.02721) + PUU_ZETA (x(U) 0.14262) |
| PuU-10Kur.tdb | 397.62 | BETA_PU (x(U) 0.00225) + ALPHA_PU (x(U) 0.00225) + PUU_ZETA (x(U) 0.14407) |
| PuU-15Per.tdb | 980.56 | BCC_A2 (x(U) 0.69633) + PUU_ETA (x(U) 0.71207) + TETRAGONAL_U (x(U) 0.73153) |
| PuU-15Per.tdb | 862.22 | PUU_ETA (x(U) 0.74013) + PUU_ZETA (x(U) 0.74134) + TETRAGONAL_U (x(U) 0.75768) |
| PuU-15Per.tdb | 833.33 | PUU_ZETA (x(U) 0.76461) + TETRAGONAL_U (x(U) 0.83253) + ORTHORHOMBIC_A20 (x(U) 0.87526) |
| PuU-15Per.tdb | 729.7 | TETRAGONAL_A6 (x(U) 0.00391) + BCC_A2 (x(U) 0.01408) + PUU_ETA (x(U) 0.02018) |
| PuU-15Per.tdb | 715.87 | FCC_A1 (x(U) 0.00332) + TETRAGONAL_A6 (x(U) 0.00375) + PUU_ETA (x(U) 0.02005) |
| PuU-15Per.tdb | 591.26 | GAMMA_PU (x(U) 0.00206) + FCC_A1 (x(U) 0.0025) + PUU_ETA (x(U) 0.02262) |
| PuU-15Per.tdb | 553.62 | GAMMA_PU (x(U) 0.00264) + BETA_PU (x(U) 0.01593) + PUU_ETA (x(U) 0.03349) |
| PuU-15Per.tdb | 551.71 | BETA_PU (x(U) 0.01665) + PUU_ETA (x(U) 0.03502) + PUU_ZETA (x(U) 0.30998) |
| PuU-15Per.tdb | 397.46 | ALPHA_PU (x(U) 0) + BETA_PU (x(U) 4.300e-4) + PUU_ZETA (x(U) 0.27107) |
| PuU-23Fou.tdb | 956.63 | BCC_A2 (x(U) 0.65942) + PUU_ETA (x(U) 0.67471) + TETRAGONAL_U (x(U) 0.68067) |
| PuU-23Fou.tdb | 854.59 | PUU_ZETA (x(U) 0.73703) + PUU_ETA (x(U) 0.77956) + TETRAGONAL_U (x(U) 0.79439) |
| PuU-23Fou.tdb | 840.59 | PUU_ZETA (x(U) 0.74749) + TETRAGONAL_U (x(U) 0.82026) + ORTHORHOMBIC_A20 (x(U) 0.86227) |
| PuU-23Fou.tdb | 712.8 | FCC_A1 (x(U) 0.00375) + BCC_A2 (x(U) 0.02173) + PUU_ETA (x(U) 0.03566) |
| PuU-23Fou.tdb | 589.42 | GAMMA_PU (x(U) 0) + FCC_A1 (x(U) 9.000e-4) + PUU_ETA (x(U) 0.01322) |
| PuU-23Fou.tdb | 525.69 | GAMMA_PU (x(U) 0) + BETA_PU (x(U) 0.00825) + PUU_ETA (x(U) 0.01952) |
| PuU-23Fou.tdb | 504.5 | BETA_PU (x(U) 0.01323) + PUU_ETA (x(U) 0.03103) + PUU_ZETA (x(U) 0.26574) |
| PuU-23Fou.tdb | 396.75 | ALPHA_PU (x(U) 0) + BETA_PU (x(U) 0.00245) + PUU_ZETA (x(U) 0.2621) |
| PuU-99Kur.tdb | 974.11 | BCC_A2 (x(U) 0.72827) + PUU_ETA (x(U) 0.73473) + TETRAGONAL_U (x(U) 0.74801) |
| PuU-99Kur.tdb | 867.91 | PUU_ZETA (x(U) 0.71816) + PUU_ETA (x(U) 0.73935) + TETRAGONAL_U (x(U) 0.75411) |
| PuU-99Kur.tdb | 840.59 | PUU_ZETA (x(U) 0.74749) + TETRAGONAL_U (x(U) 0.82026) + ORTHORHOMBIC_A20 (x(U) 0.86227) |
| PuU-99Kur.tdb | 731.61 | TETRAGONAL_A6 (x(U) 0.00438) + BCC_A2 (x(U) 0.01392) + PUU_ETA (x(U) 0.02068) |
| PuU-99Kur.tdb | 716.26 | FCC_A1 (x(U) 0.00384) + TETRAGONAL_A6 (x(U) 0.00426) + PUU_ETA (x(U) 0.02058) |
| PuU-99Kur.tdb | 593.06 | GAMMA_PU (x(U) 0.00338) + FCC_A1 (x(U) 0.00338) + PUU_ETA (x(U) 0.02344) |
| PuU-99Kur.tdb | 552.19 | GAMMA_PU (x(U) 0.00478) + BETA_PU (x(U) 0.01784) + PUU_ETA (x(U) 0.03593) |
| PuU-99Kur.tdb | 544.8 | BETA_PU (x(U) 0.0212) + PUU_ETA (x(U) 0.04235) + PUU_ZETA (x(U) 0.26981) |
| PuU-99Kur.tdb | 396.75 | ALPHA_PU (x(U) 0) + BETA_PU (x(U) 0.00245) + PUU_ZETA (x(U) 0.2621) |

Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/PU/PU-U.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/PU/PU-U.json) · [CALPHAD hull PuU-10Kur](https://data.orchid-project.org/hulls/calphad-sgte/PU/PU-U--PuU-10Kur.json) · [CALPHAD hull PuU-15Per](https://data.orchid-project.org/hulls/calphad-sgte/PU/PU-U--PuU-15Per.json) · [CALPHAD hull PuU-99Kur](https://data.orchid-project.org/hulls/calphad-sgte/PU/PU-U--PuU-99Kur.json)

## Other properties

### Heat capacity / entropy / enthalpy (6)

Table: Heat capacity / entropy / enthalpy, Pu–U system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Heat capacity; _printed: Cp_ | 38.5 J/mol-atom/K | 673 | α; _alloy: Pu 0.1, U 0.9_ | experimental | [1] Kurata 1999; _cites ref. 11Chi_ | Table 3, p. 17, row 2; `ORC-K3HZTEHG2L.f8e0f3` |  |
| Heat capacity; _printed: Cp_ | 37.5 J/mol-atom/K | 673 | α; _alloy: Pu 0.1, U 0.9_ | model | [1] Kurata 1999 | Table 3, p. 17, row 1; `ORC-TUPPEUSP3G.090ff3` |  |
| Heat capacity; _printed: Cp_ | 42.1 J/mol-atom/K | 773 | α; _alloy: Pu 0.1, U 0.9_ | experimental | [1] Kurata 1999; _cites ref. 11Chi_ | Table 3, p. 17, row 4; `ORC-AZHIIJFVVN.0f8013` |  |
| Heat capacity; _printed: Cp_ | 40.8 J/mol-atom/K | 773 | α; _alloy: Pu 0.1, U 0.9_ | model | [1] Kurata 1999 | Table 3, p. 17, row 3; `ORC-NP3TPDQFGJ.c2bf44` |  |
| Heat capacity; _printed: Cp_ | 44.5 J/mol-atom/K | 840 | α; _alloy: Pu 0.1, U 0.9_ | experimental | [1] Kurata 1999; _cites ref. 11Chi_ | Table 3, p. 17, row 6; `ORC-KSXPAH2RSB.4db829` |  |
| Heat capacity; _printed: Cp_ | 43.3 J/mol-atom/K | 840 | α; _alloy: Pu 0.1, U 0.9_ | model | [1] Kurata 1999 | Table 3, p. 17, row 5; `ORC-QZJQT2XAUD.2a0d87` |  |

## Sources

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

1. Masaki Kurata, Thermodynamic assessment of the Pu-U, Pu-Zr, and Pu-U-Zr systems, Calphad 23, 305-337 (1999). [doi:10.1016/s0364-5916(00)00004-3](https://doi.org/10.1016/s0364-5916%2800%2900004-3)

## 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/).