# O–Ti system > O–Ti system: 35 accepted literature values (invariant reaction 35) and 0 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote. HTML: https://data.orchid-project.org/systems/O-TI.html · Markdown: https://data.orchid-project.org/systems/O-TI.md 35 accepted literature values from 1 paper(s) (experimental 13, model 22); 0 calculated phase diagram(s). 9 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/O-TI.json) · [CSV](https://data.orchid-project.org/systems/O-TI.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#O-TI) · [phases (22)](https://data.orchid-project.org/phases/pages/O-TI.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/O-TI.html) · [Markdown](https://data.orchid-project.org/systems/O-TI.md) Table: Accepted values by evidence class | Evidence class | Values | |---|---:| | experimental | 13 | | model | 22 | Table: Accepted values by property group | Property group | Values | |---|---:| | invariant reaction | 35 | Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/O/O-TI.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/O/O-TI.json) ## Invariant reactions (literature) Table: Invariant reactions reported in the literature for the O–Ti system (35) | T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote | |---:|---|---|---|---|---|---| | 2168.3 | congruent melting: hcp = liquid | hcp: O 0.299; liquid: O 0.299 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 4; `ORC-P7W2YAD3T5` | | | 2158 | congruent melting: hcp = liquid | hcp: O 0.24; liquid: O 0.24 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 3; `ORC-ICF5EYWZBZ` | | | 2143 | congruent melting: TiO2 = liquid | TiO2: O 0.6667; liquid: O 0.6667 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 16; `ORC-SSLYYKLABQ` | | | 2142.3 | congruent melting: TiO2 = liquid | TiO2: O 0.6662; liquid: O 0.6662 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 17; `ORC-ZILNOUZJBP` | | | 2138.6 | liquid = TiO2-x + gas | L: Ti 0.3316; TiO2-x: Ti 0.3337; gas: Ti 1.000e-4 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 8; `ORC-JW2UJNDIWV` | | | 2115 | congruent melting: liquid = Ti2O3 | liquid: O 0.6; Ti2O3: O 0.6 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 9; `ORC-7ELV2OYZUC` | | | 2112.3 | congruent melting: liquid = Ti2O3 | liquid: O 0.6; Ti2O3: O 0.6 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 10; `ORC-WWTXNENSPR` | | | 2047.7 | congruent melting: Ti3O5 = liquid | Ti3O5: O 0.625; liquid: O 0.625 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 13; `ORC-E7HVYU3WGS` | | | 2043.7 | liquid + hcp = TiOx | liquid: O 0.4487; hcp: O 0.3307; TiOx: O 0.3979 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 6; `ORC-KKWF4IIICF` | | | 2043 | liquid + hcp = TiOx | liquid: O 0.55; hcp: O 0.314; TiOx: O 0.345 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 5; `ORC-HUVCIHKRK7` | | | 2043 | liquid = Ti2O3 + Ti3O5 | liquid: O 0.63; Ti2O3: O 0.602; Ti3O5: O 0.6225 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 11; `ORC-WRNUEAXTIJ` | | | 2039.7 | liquid = Ti2O3 + Ti3O5 | liquid: O 0.6198; Ti2O3: O 0.6; Ti3O5: O 0.6225 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 12; `ORC-N5QURWCLXO` | | | 2030.4 | liquid + TiO2-x = Ti20O39 | L: Ti 0.3457; TiO2-x: Ti 0.3356; Ti20O39: Ti 0.339 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 7; `ORC-HEI6Y4LW6A` | | | 2016.42 | liquid + hcp = bcc | liquid: O 0.0605; hcp: O 0.1434; bcc: O 0.0798 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 2; `ORC-RL7R22SUGX` | | | 1993 | liquid + hcp = bcc | liquid: O 0.05; hcp: O 0.13; bcc: O 0.08 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 1; `ORC-E2K5XBSBED` | | | 1993 | liquid = TiOx + Ti2O3 | liquid: O 0.57; TiOx: O 0.545; Ti2O3: O 0.598 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 7; `ORC-ZXWIO3GUO3` | | | 1992.1 | liquid = TiOx + Ti2O3 | liquid: O 0.5587; TiOx: O 0.553; Ti2O3: O 0.6 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 8; `ORC-HWXJMFK7CT` | | | 1971.3 | liquid + Ti20O39 = Ti10O19 | L: Ti 0.3524; Ti20O39: Ti 0.339; Ti10O19: Ti 0.3448 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 6; `ORC-5AZCIGRWAK` | | | 1965.6 | liquid + Ti10O19 = Ti9O17 | L: Ti 0.3533; Ti10O19: Ti 0.3448; Ti9O17: Ti 0.3461 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 5; `ORC-MNBJSGKV54` | | | 1962.4 | liquid + Ti9O17 = Ti8O15 | L: Ti 0.3539; Ti9O17: Ti 0.3461; Ti8O15: Ti 0.3478 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 4; `ORC-3BBPVMYRMN` | | | 1957.6 | liquid + Ti8O15 = Ti7O13 | L: Ti 0.3549; Ti8O15: Ti 0.3478; Ti7O13: Ti 0.35 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 3; `ORC-4BZGGP74DC` | | | 1954.7 | liquid + Ti7O13 = Ti6O11 | L: Ti 0.3557; Ti7O13: Ti 0.35; Ti6O11: Ti 0.3529 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 2; `ORC-X6BPWIKXJ3` | | | 1950.5 | liquid + Ti6O11 = Ti5O9 | L: Ti 0.3573; Ti6O11: Ti 0.3529; Ti5O9: Ti 0.3571 | model | [1] Cancarevic 2007 | Table 5, p. 11, row 1; `ORC-TI7JF7VXHS` | | | 1947.7 | liquid = Ti3O5 + Ti5O9 | liquid: O 0.6401; Ti3O5: O 0.625; Ti5O9: O 0.6429 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 15; `ORC-P7LXYZCS4K` | | | 1943 | liquid = Ti3O5 + Ti5O9 | liquid: O 0.64; Ti3O5: O 0.625 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 14; `ORC-42WHNT4WDR` | | | 1940.4 | Ti3O5 + Ti5O9 = Ti4O7 | Ti3O5: O 0.625; Ti5O9: O 0.6429; Ti4O7: O 0.6364 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 25; `ORC-LLVRAAJLQ5` | | | 1940 | Ti3O5 + Ti5O9 = Ti4O7 | Ti3O5: O 0.625; Ti5O9: O 0.6429; Ti4O7: O 0.6364 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 24; `ORC-LKMIA4KVYM` | | | 1213 | hcp + TiOx = α-TiO | hcp: O 0.333; TiOx: O 0.51; α-TiO: O 0.5 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 18; `ORC-SHW2HSACZ6` | | | 1208.6 | hcp + TiOx = α-TiO | hcp: O 0.3333; TiOx: O 0.5028; α-TiO: O 0.5 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 19; `ORC-VMY62SVUMH` | | | 1193 | hcp + α-TiO = Ti3O2 | hcp: O 0.324; α-TiO: O 0.5; Ti3O2: O 0.4 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 20; `ORC-HFP2F2PSBO` | | | 1193 | hcp + α-TiO = Ti3O2 | hcp: O 0.3333; α-TiO: O 0.5; Ti3O2: O 0.4 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 21; `ORC-SY6AOBUK56` | | | 1000 | Ti3O5 = Ti2O3 + Ti4O7 | Ti3O5: O 0.625; Ti2O3: O 0.6; Ti4O7: O 0.6364 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 26; `ORC-RLINDTXSTA` | | | 778.4 | Ti3O5 = Ti2O3 + Ti4O7 | Ti3O5: O 0.625; Ti2O3: O 0.6; Ti4O7: O 0.6364 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 27; `ORC-KTNTGSCDFK` | | | 733.5 | TiOx = α-TiO + Ti2O3 | TiOx: O 0.5411; α-TiO: O 0.5; Ti2O3: O 0.6 | model | [1] Cancarevic 2007 | Table 4, p. 10, row 23; `ORC-OLAPJTRTVA` | | | 733 | TiOx = α-TiO + Ti2O3 | TiOx: O 0.545; α-TiO: O 0.5; Ti2O3: O 0.6 | experimental | [1] Cancarevic 2007; _cites Murray 1987_ [doi](https://doi.org/10.1007/bf02873201) | Table 4, p. 10, row 22; `ORC-U2266QCHUC` | | ## Sources Reporting papers the values were read from (a value cited from another work names that work in its row). 1. M. Cancarevic, M. Zinkevich, F. Aldinger, Thermodynamic description of the Ti–O system using the associate model for the liquid phase, Calphad 31, 330-342 (2007). [doi:10.1016/j.calphad.2007.01.009](https://doi.org/10.1016/j.calphad.2007.01.009) ## 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/).