# U–N system > U–N system: 0 accepted literature values (none) and 1 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote. HTML: https://data.orchid-project.org/systems/U-N.html · Markdown: https://data.orchid-project.org/systems/U-N.md 0 accepted literature values from 0 paper(s); 1 calculated phase diagram(s). Data: [interactive phase diagram](https://orchid-project.org/phase-diagrams/#U-N/UN-00Che.json) · [Markdown](https://data.orchid-project.org/systems/U-N.md) ## 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 | |---|---|---|---| | UN-00Che.tdb | P.-Y. Chevalier, E. Fischer, B. Cheynet, J. Nucl. Mater., 280, 136-50(2000). [doi:10.1016/S0022-3115(00)00043-X](https://doi.org/10.1016/S0022-3115%2800%2900043-X) | `690d73c71200efc98685de28f29a554b95a8294cbcbb5b3252b67e818c80b744` | [viewer](https://orchid-project.org/phase-diagrams/#U-N/UN-00Che.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/UN-00Che.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/UN-00Che.json) | Table: Calculated three-phase invariants (model, mole fraction of the second component) | TDB file | T (K) | Phases at the invariant | |---|---:|---| | UN-00Che.tdb | 3066.3 | LIQUID (x(N) 0.42477) + FCC_B1 (x(N) 0.49847) + GAS (x(N) 0.99968) | | UN-00Che.tdb | 1626.26 | FCC_B1 (x(N) 0.5) + U2N3_D52 (x(N) 0.58678) + GAS (x(N) 1) | | UN-00Che.tdb | 1626.26 | FCC_B1 (x(N) 0.5) + U2N3_D52 (x(N) 0.58678) + N2GAS (x(N) 1) | | UN-00Che.tdb | 1407.88 | BCC_A2 (x(N) 0) + LIQUID (x(N) 6.000e-5) + FCC_B1 (x(N) 0.49971) | | UN-00Che.tdb | 1175.02 | U2N3_D52 (x(N) 0.58678) + U2N3_ALPHA (x(N) 0.60363) + N2GAS (x(N) 1) | | UN-00Che.tdb | 1175.02 | U2N3_D52 (x(N) 0.58678) + U2N3_ALPHA (x(N) 0.60363) + GAS (x(N) 1) | | UN-00Che.tdb | 1048.99 | TETRAGONAL_U (x(N) 0) + BCC_A2 (x(N) 0) + FCC_B1 (x(N) 0.49996) | | UN-00Che.tdb | 1038.13 | FCC_B1 (x(N) 0.5) + U2N3_D52 (x(N) 0.58678) + U2N3_ALPHA (x(N) 0.60004) | | UN-00Che.tdb | 942.02 | ORTHORHOMBIC_A20 (x(N) 0) + TETRAGONAL_U (x(N) 0) + FCC_B1 (x(N) 0.49999) | ## Please cite - 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 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 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; 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). 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_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_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=\, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).