# Co–Pt system > Co–Pt system: 18 accepted literature values (crystal structure 10, formation 3, phase transition 3, mixing / partial 1) and 3 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote. HTML: https://data.orchid-project.org/systems/CO-PT.html · Markdown: https://data.orchid-project.org/systems/CO-PT.md 18 accepted literature values from 1 paper(s) (experimental 10, model 2, DFT 6); 3 calculated phase diagram(s). 1 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/CO-PT.json) · [CSV](https://data.orchid-project.org/systems/CO-PT.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#CO-PT) · [interactive phase diagram](https://orchid-project.org/phase-diagrams/#CO-PT/CoPt-01Oik.json) · [phases (7)](https://data.orchid-project.org/phases/pages/CO-PT.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/CO-PT.html) · [Markdown](https://data.orchid-project.org/systems/CO-PT.md) Table: Accepted values by evidence class | Evidence class | Values | |---|---:| | experimental | 10 | | model | 2 | | DFT | 6 | Table: Accepted values by property group | Property group | Values | |---|---:| | phase transition | 3 | | formation | 3 | | mixing / partial | 1 | | crystal structure | 10 | | other property | 1 | ## 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 | |---|---|---|---| | CoPt-01Oik.tdb | K. Oikawa, G.W. Qin, T. Ikeshoji, O. Kitakami, Y. Shimada, K. Ishida, K. Fukamichi, J. Magn. Magn. Mater., 236, 220-33(2001). [doi:10.1016/S0304-8853(00)00520-5](https://doi.org/10.1016/S0304-8853%2800%2900520-5) | `adf708dbafc5b2c33e1c38c29470eecad45f99bc0f546e31c1dc5b079e13b2bd` | [viewer](https://orchid-project.org/phase-diagrams/#CO-PT/CoPt-01Oik.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CoPt-01Oik.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CoPt-01Oik.json) | | CoPt-11Kim.tdb | D. Kim, J.E. Saal, L. Zhou, S. Shang, Y. Du, Z.-K. Liu, Calphad, 35, 323-30(2011). [doi:10.1016/j.calphad.2011.04.005](https://doi.org/10.1016/j.calphad.2011.04.005) | `335cf2628217f37fe82d25ddcd19a8fc5d7d507ef2e61b63faf15962523eced6` | [viewer](https://orchid-project.org/phase-diagrams/#CO-PT/CoPt-11Kim.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CoPt-11Kim.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CoPt-11Kim.json) | | CoPt-90Spe-LB.tdb | P.J. Spencer, unpublished, 1990. | `8a9bf4d4f4636b8994e37943ba8aff05c80e6d02794f1c610e7343ae0dee89c6` | [viewer](https://orchid-project.org/phase-diagrams/#CO-PT/CoPt-90Spe-LB.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CoPt-90Spe-LB.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CoPt-90Spe-LB.json) | Table: Calculated three-phase invariants (model, mole fraction of the second component) | TDB file | T (K) | Phases at the invariant | |---|---:|---| | CoPt-11Kim.tdb | 962.79 | FCC_4SL (x(Pt) 0.57621) + FCC_4SL#2 (x(Pt) 0.61122) + FCC_4SL#3 (x(Pt) 0.6201) | | CoPt-11Kim.tdb | 962.79 | FCC_4SL (x(Pt) 0.57621) + FCC_A1 (x(Pt) 0.61122) + FCC_4SL#2 (x(Pt) 0.6201) | | CoPt-11Kim.tdb | 652.1 | HCP_A3 (x(Pt) 0.15243) + FCC_A1 (x(Pt) 0.16793) + FCC_4SL (x(Pt) 0.22638) | | CoPt-11Kim.tdb | 652.1 | HCP_A3 (x(Pt) 0.15243) + FCC_4SL#2 (x(Pt) 0.16793) + FCC_4SL (x(Pt) 0.22638) | | CoPt-90Spe-LB.tdb | 673.57 | HCP_A3 (x(Pt) 0.36339) + FCC_A1 (x(Pt) 0.37848) + COPT_L10 (x(Pt) 0.39722) | | CoPt-90Spe-LB.tdb | 446.9 | COPT_L10 (x(Pt) 0.63247) + FCC_A1 (x(Pt) 0.65973) + COPT3_L12 (x(Pt) 0.69701) | Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/CO/CO-PT.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/CO/CO-PT.json) · [CALPHAD hull CoPt-01Oik](https://data.orchid-project.org/hulls/calphad-sgte/CO/CO-PT--CoPt-01Oik.json) · [CALPHAD hull CoPt-90Spe-LB](https://data.orchid-project.org/hulls/calphad-sgte/CO/CO-PT--CoPt-90Spe-LB.json) ## 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, Co–Pt system (3) | Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote | |---|---|---:|---:|---|---:|---:|---|---|---| | CoPt | | -13.6 per mol-atom ± 0.7 | 914 | experimental | | | [1] Kim 2011; _cites Oriani 1962_ [doi](https://doi.org/10.1016/0001-6160%2862%2990102-5) | Table 2, p. 3, row 16; `ORC-GIYTSCDO2K.8b23fd` | | | CoPt | | -12.265 kJ/mol-atom | 914 | DFT | | | [1] Kim 2011 | Table 2, p. 3, row 15; `ORC-SM7S5KGROG` | | | CoPt3 | | -12.8 per mol-atom ± 1.63 | 914 | experimental | | | [1] Kim 2011; _cites Oriani 1962_ [doi](https://doi.org/10.1016/0001-6160%2862%2990102-5) | Table 2, p. 3, row 16; `ORC-GIYTSCDO2K.e42b94` | | ## Other properties ### Phase transition (3) Table: Phase transition, Co–Pt system | Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote | |---|---:|---:|---|---|---|---|---| | Phase transition | 822 K | 822 | Co3Pt | model | [1] Kim 2011 | p. 5; `ORC-MVXAE2DJ6I` | “Co3 Pt is predicted to be stable up to about 822 K.” | | Phase transition | 840 K | 840 | congruent transformation | experimental | [1] Kim 2011; _cites Inden 1983_ | p. 5; `ORC-2GN6RCBU3A` | “This behavior is similar to that measured by Inden \[25\] with a congruent temperature of approximately 840 K.” | | Phase transition | 1104 K | 1104 | other | experimental | [1] Kim 2011 | p. 6; `ORC-RIRD4VLSIT` | “The calculated LRO parameter for L10 according to Eq. (12) is plotted in Fig. 9 along with the experimental data \[24\] with the temperature normalized by the order/disorder transition temperature of the L10 CoPt phase of 1104 K, showing a good agreement.” | ### Mixing / partial (1) Table: Mixing / partial, Co–Pt system | Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote | |---|---:|---:|---|---|---|---|---| | Enthalpy of mixing; _printed: ΔHmix_ | -8.651 kJ/mol-atom | 300 | Co3Pt; _alloy: Pt 0.25_ | DFT | [1] Kim 2011 | Table 2, p. 3, row 17; `ORC-LBIEX7D7TT` | | ### Crystal structure (10) Table: Crystal structure, Co–Pt system | Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote | |---|---:|---:|---|---|---|---|---| | Lattice a; _printed: a_ | 3.654 Å | | Co3Pt; _alloy: Pt 0.25_ | DFT | [1] Kim 2011 | Table 2, p. 3, row 1; `ORC-V27RV5CYCF.db7e95` | | | Lattice a; _printed: a_ | 3.664 Å | | Co3Pt; _alloy: Pt 0.25_ | experimental | [1] Kim 2011; _cites Capitan 1999_ [doi](https://doi.org/10.1107/s0021889899009887) | Table 2, p. 3, row 2; `ORC-XUMWTQJRL4.cccfc6` | | | Lattice a; _printed: a_ | 3.806 Å | | CoPt; _alloy: Pt 0.5_ | experimental | [1] Kim 2011; _cites Galanakis 2000_ [doi](https://doi.org/10.1103/physrevb.62.6475) | Table 2, p. 3, row 3; `ORC-JHEHM3DFYG` | | | Lattice a; _printed: a_ | 3.809 Å | | CoPt; _alloy: Pt 0.5_ | DFT | [1] Kim 2011 | Table 2, p. 3, row 1; `ORC-V27RV5CYCF.4fde13` | | | Lattice a; _printed: a_ | 3.811 Å | | CoPt; _alloy: Pt 0.5_ | experimental | [1] Kim 2011; _cites Capitan 1999_ [doi](https://doi.org/10.1107/s0021889899009887) | Table 2, p. 3, row 2; `ORC-XUMWTQJRL4.784e91` | | | Lattice a; _printed: a_ | 3.885 Å | | CoPt3; _alloy: Pt 0.75_ | DFT | [1] Kim 2011 | Table 2, p. 3, row 1; `ORC-V27RV5CYCF.4ba2a2` | | | Lattice a; _printed: a_ | 3.857 Å | | CoPt3; _alloy: Pt 0.75_ | experimental | [1] Kim 2011; _cites Capitan 1999_ [doi](https://doi.org/10.1107/s0021889899009887) | Table 2, p. 3, row 2; `ORC-XUMWTQJRL4.b745c8` | | | Lattice c; _printed: c_ | 3.708 Å | | CoPt; _alloy: Pt 0.5_ | DFT | [1] Kim 2011 | Table 2, p. 3, row 4; `ORC-DMUHJZNF4E` | | | Lattice c; _printed: c_ | 3.684 Å | | CoPt; _alloy: Pt 0.5_ | experimental | [1] Kim 2011; _cites Galanakis 2000_ [doi](https://doi.org/10.1103/physrevb.62.6475) | Table 2, p. 3, row 6; `ORC-FVDHWTECZC` | | | Lattice c; _printed: c_ | 3.694 Å | | CoPt; _alloy: Pt 0.5_ | experimental | [1] Kim 2011; _cites Leroux 1988_ | Table 2, p. 3, row 5; `ORC-VNZGPGSBDD` | | ### Other property (1) Table: Other property, Co–Pt system | Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote | |---|---:|---:|---|---|---|---|---| | Other; _printed: enthalpy of transformation_ | -3.303 kJ/mol-atom | 783 | L10 + fcc | model | [1] Kim 2011 | p. 5; `ORC-K6TT5TWMWV.025c14` | “The calculated enthalpy for the disordered fcc phase to L10 transformation in CoPt compound at 783 K from the current modeling is -3.303 kJ/mol-atom which is also in a good agreement with the experimental data (-3.1 ± 0.2 kJ/mol-atom) in the literature \[16\].” | ## Sources Reporting papers the values were read from (a value cited from another work names that work in its row). 1. DongEung Kim, James E. Saal, Liangcai Zhou, ShunLi Shang, Yong Du, Zi-Kui Liu, Thermodynamic modeling of fcc order/disorder transformations in the Co–Pt system, Calphad 35, 323-330 (2011). [doi:10.1016/j.calphad.2011.04.005](https://doi.org/10.1016/j.calphad.2011.04.005) ## 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-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=\, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).