# B–Ca system > B–Ca system: 9 accepted literature values (formation 6, invariant reaction 3) 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-CA.html · Markdown: https://data.orchid-project.org/systems/B-CA.md 9 accepted literature values from 1 paper(s) (model 9); 0 calculated phase diagram(s). Data: [JSON](https://data.orchid-project.org/literature/systems/B-CA.json) · [CSV](https://data.orchid-project.org/systems/B-CA.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#B-CA) · [phases (7)](https://data.orchid-project.org/phases/pages/B-CA.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/B-CA.html) · [Markdown](https://data.orchid-project.org/systems/B-CA.md) Table: Accepted values by evidence class | Evidence class | Values | |---|---:| | model | 9 | Table: Accepted values by property group | Property group | Values | |---|---:| | invariant reaction | 3 | | formation | 6 | Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/B/B-CA.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/B/B-CA.json) ## Invariant reactions (literature) Table: Invariant reactions reported in the literature for the B–Ca system (3) | T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote | |---:|---|---|---|---|---|---| | 1388 | CaB6 + β(B) = α(B) | CaB6: Ca 0.143; β(B): Ca 0; α(B): Ca 0 | model | [1] Shang 2007 | Table 4, p. 5, row 5; `ORC-5AROFYWVIF` | | | 1115 | liq1 = CaB6 + bcc(Ca) | liq1: Ca 1; CaB6: Ca 0.143; bcc(Ca): Ca 1 | model | [1] Shang 2007 | Table 4, p. 5, row 6; `ORC-EL4SRXI7FT` | | | 716 | CaB6 + bcc(Ca) = fcc(Ca) | CaB6: Ca 0.143; bcc(Ca): Ca 1; fcc(Ca): Ca 1 | model | [1] Shang 2007 | Table 4, p. 5, row 7; `ORC-YFEUJXC6BR` | | ## 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–Ca system (3) | Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote | |---|---|---:|---:|---|---:|---:|---|---|---| | CaB6 | [CaB6](https://data.orchid-project.org/compounds/CaB6.html) | -41.2015 kJ/mol-atom | 298.15 | model | -39.347 (mp-aaaaabhh) | -39.822 (oqmd-5116) | [1] Shang 2007 | Table 3, p. 3, row 1; `ORC-YQYRMYDNK6.1ff180` | | | CaB6 | [CaB6](https://data.orchid-project.org/compounds/CaB6.html) | -41.1829 kJ/mol-atom | 298.15 | model | -39.347 (mp-aaaaabhh) | -39.822 (oqmd-5116) | [1] Shang 2007 | Table 3, p. 3, row 3; `ORC-SNQ6FLFJ4Z.6b8958` | | | CaB6 | [CaB6](https://data.orchid-project.org/compounds/CaB6.html) | -40.193 kJ/mol-atom | 298.15 | model | -39.347 (mp-aaaaabhh) | -39.822 (oqmd-5116) | [1] Shang 2007 | Table 3, p. 3, row 4; `ORC-2QV6UM5WWM.21d819` | | ## Other properties ### Formation (3) Table: Formation, B–Ca system | Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote | |---|---:|---:|---|---|---|---|---| | Entropy of formation; _printed: ΔfS298_ | 2.67361 J/mol-atom/K | 298.15 | CaB6; _alloy: Ca 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 4; `ORC-2QV6UM5WWM.dd776a` | | | Entropy of formation; _printed: ΔfS298_ | 0.141774 J/mol-atom/K | 298.15 | CaB6; _alloy: Ca 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 3; `ORC-SNQ6FLFJ4Z.563a78` | | | Entropy of formation; _printed: ΔfS298_ | 0.191183 J/mol-atom/K | 298.15 | CaB6; _alloy: Ca 0.142857_ | model | [1] Shang 2007 | Table 3, p. 3, row 1; `ORC-YQYRMYDNK6.6f4c05` | | ## 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=\, carrying only the record id, source and value; [how to contribute](https://orchid-project.org/contribute/).