# Cu–O system

> Cu–O system: 355 accepted literature values (model expression 174, invariant reaction 54, formation 39, activity / EMF / Gibbs energy 38) and 3 calculated phase diagram(s) from ORCHID, each value with evidence class, source, page and quote.

HTML: https://data.orchid-project.org/systems/CU-O.html · Markdown: https://data.orchid-project.org/systems/CU-O.md

355 accepted literature values from 2 paper(s) (experimental 280, model 75); 3 calculated phase diagram(s). 22 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/CU-O.json) · [CSV](https://data.orchid-project.org/systems/CU-O.csv) · [interactive explorer](https://orchid-project.org/data-explorer/#CU-O) · [interactive phase diagram](https://orchid-project.org/phase-diagrams/#CU-O/CuO-14Mag.json) · [phases (10)](https://data.orchid-project.org/phases/pages/CU-O.html) · [papers (bibliography)](https://data.orchid-project.org/bibliography/pages/systems/CU-O.html) · [Markdown](https://data.orchid-project.org/systems/CU-O.md)

Table: Accepted values by evidence class

| Evidence class | Values |
|---|---:|
| experimental | 280 |
| model | 75 |

Table: Accepted values by property group

| Property group | Values |
|---|---:|
| invariant reaction | 54 |
| phase transition | 13 |
| formation | 39 |
| heat capacity / entropy / enthalpy | 37 |
| activity / EMF / Gibbs energy | 38 |
| model expression | 174 |

## 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 |
|---|---|---|---|
| CuO-14Mag.tdb | H. Magnusson, K. Frisk, Calphad, 47, 148-60(2014). [doi:10.1016/j.calphad.2014.09.004](https://doi.org/10.1016/j.calphad.2014.09.004) | `c359243f819163487dee47e2c28697d846db9d0456d9ede289d84dd7b0ed5f3a` | [viewer](https://orchid-project.org/phase-diagrams/#CU-O/CuO-14Mag.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CuO-14Mag.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CuO-14Mag.json) |
| CuO-92Bou.tdb | A. Boudene, K. Hack, A. Mohammad, D. Neuschuetz, E. Zimmermann, Z. Metallkd., 83, 663-68(1992). [doi:10.1515/ijmr-1992-830905](https://doi.org/10.1515/ijmr-1992-830905) | `01c48e87b93fb30f817411232690b694a306f3b90f586840e3ef2d4366420673` | [viewer](https://orchid-project.org/phase-diagrams/#CU-O/CuO-92Bou.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CuO-92Bou.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CuO-92Bou.json) |
| CuO-94Hal.tdb | B. Hallstedt, D. Risold and L.J. Gauckler, J. Phase Equilib., 15, 483-99(1994). [doi:10.1007/BF02649399](https://doi.org/10.1007/BF02649399) | `59102ffec95449e3ff1a60226d9369eb93d38b3ce8ef47fbd7332ab32b087b2a` | [viewer](https://orchid-project.org/phase-diagrams/#CU-O/CuO-94Hal.json) · [TDB](https://orchid-project.org/data/databases/sgte-binary/CuO-94Hal.tdb) · [JSON](https://data.orchid-project.org/phase-diagrams/sgte/CuO-94Hal.json) |

Convex hulls: [Materials Project DFT hull](https://data.orchid-project.org/hulls/dft-mp/CU/CU-O.json) · [OQMD DFT hull](https://data.orchid-project.org/hulls/dft-oqmd/CU/CU-O.json)

## Invariant reactions (literature)

Table: Invariant reactions reported in the literature for the Cu–O system (54)

| T (K) | Reaction / phases | Compositions (mole fraction) | Class | Source | Location | Quote |
|---:|---|---|---|---|---|---|
| 1498 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.096; L1: O 0.309 | experimental | [1] Hallstedt 1994; _cites Taskinen 1984_ | Table 2, p. 6, row 21; `ORC-237ROYO6PD` |  |
| 1498 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.092; L1: O 0.311 | model | [1] Hallstedt 1994 | Table 2, p. 6, row 24; `ORC-BEE2GJSUZ6` |  |
| 1497 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.099; L1: O 0.307 | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 23; `ORC-SCPG4YRJWH` |  |
| 1496 | monotectic: L2 -> L1 + Cu2O (monotectic) |  | experimental | [1] Hallstedt 1994; _cites Kemori 1979_ [doi](https://doi.org/10.1016/0021-9614%2879%2990145-9) | Table 2, p. 6, row 18; `ORC-NQJKSB4N3H` |  |
| 1495 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.096; L1: O 0.308 | experimental | [1] Hallstedt 1994; _cites Kayahara 1981_ [doi](https://doi.org/10.2320/jinstmet1952.42.5_527) | Table 2, p. 6, row 20; `ORC-CFYMJPFKPV` |  |
| 1495 | monotectic: L2 -> L1 + Cu2O (monotectic) |  | experimental | [1] Hallstedt 1994; _cites Kemori 1980_ [doi](https://doi.org/10.2320/matertrans1960.21.275) | Table 2, p. 6, row 19; `ORC-DYPDRUETG2` |  |
| 1495 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.097; L1: O 0.308 | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 2, p. 6, row 22; `ORC-EYNKPXRG7J` |  |
| 1493 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.094; L1: O 0.311 | experimental | [1] Hallstedt 1994; _cites Kuxmann 1968_ | Table 2, p. 6, row 16; `ORC-LAIDYCOUCU` |  |
| 1490 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.095; L1: O 0.316 | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 17; `ORC-RMOG4DLT2W` |  |
| 1489 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.087; L1: O 0.313 | experimental | [1] Hallstedt 1994; _cites Osterwald 1968_ | Table 2, p. 6, row 14; `ORC-PDCMB5DZXB` |  |
| 1489 | monotectic: L2 -> L1 + Cu2O (monotectic) |  | experimental | [1] Hallstedt 1994; _cites Osterwald 1966_ [doi](https://doi.org/10.1524/zpch.1966.49.3_5.138) | Table 2, p. 6, row 13; `ORC-QL4BQF6UHF` |  |
| 1489 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.089; L1: O 0.305 | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ [doi](https://doi.org/10.1515/ijmr-1968-590711) | Table 2, p. 6, row 15; `ORC-XPLHH56UGT` |  |
| 1473 | monotectic: L2 -> L1 + Cu2O (monotectic) |  | experimental | [1] Hallstedt 1994; _cites Vogel 1929_ | Table 2, p. 6, row 12; `ORC-JW2QZYMGBA` |  |
| 1468 | monotectic: L2 -> L1 + Cu2O (monotectic) | L2: O 0.084; L1: O 0.319 | experimental | [1] Hallstedt 1994; _cites Slade 1912_ [doi](https://doi.org/10.1098/rspa.1912.0107) | Table 2, p. 6, row 11; `ORC-BYEYPVOYBU` |  |
| 1428 | L2 + O2 -> Cu2O (in air) |  | experimental | [1] Hallstedt 1994; _cites Eric 1979_ [doi](https://doi.org/10.1007/bf02662558) | Table 2, p. 6, row 47; `ORC-6WNCSLDQ2F` |  |
| 1413 | L2 + O2 -> Cu2O (in air) | L2: O 0.369 | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 46; `ORC-WVXWT2XLZI` |  |
| 1403 | L2 + O2 -> CuO (in oxygen) | L2: O 0.39 | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 2, p. 6, row 57; `ORC-4TSUEJJKFY` |  |
| 1398 | L2 + O2 -> Cu2O (in air) | L2: O 0.378 | experimental | [1] Hallstedt 1994; _cites Osterwald 1968_ | Table 2, p. 6, row 45; `ORC-7B2IRBLOHZ` |  |
| 1397 | L2 + O2 -> Cu2O (in air) | L2: O 0.377 | model | [1] Hallstedt 1994 | Table 2, p. 6, row 50; `ORC-SNT4ZLFQCW` |  |
| 1396 | L2 + O2 -> CuO (in oxygen) | L2: O 0.393 | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 55; `ORC-3F5ONP2TI7` |  |
| 1395 | L2 + O2 -> CuO (in oxygen) | L2: O 0.397 | experimental | [1] Hallstedt 1994; _cites Osterwald 1968_ | Table 2, p. 6, row 54; `ORC-F5RDPS7XEV` |  |
| 1393 | L2 + O2 -> Cu2O (in air) | L2: O 0.377 | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 49; `ORC-FXJPY5MYVO` |  |
| 1387 | L2 + O2 -> Cu2O (in air) |  | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 2, p. 6, row 48; `ORC-L6Q3DK23C2` |  |
| 1383 | L2 + O2 -> CuO (in oxygen) |  | experimental | [1] Hallstedt 1994; _cites Vogel 1929_ | Table 2, p. 6, row 52; `ORC-ID2W2HAPJB` |  |
| 1375 | L2 + O2 -> CuO (in oxygen) | L2: O 0.392 | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 58; `ORC-6UMYPFMH6P` |  |
| 1375 | L2 + O2 -> CuO (in oxygen) | L2: O 0.392 | model | [1] Hallstedt 1994 | Table 2, p. 6, row 59; `ORC-LOAA3D2ZIR` |  |
| 1374 | L2 + O2 -> CuO (in oxygen) | L2: O 0.399 | experimental | [1] Hallstedt 1994; _cites EH 1920_ | Table 2, p. 6, row 51; `ORC-ADL5PPMYRZ` |  |
| 1371 | L2 + O2 -> CuO (in oxygen) |  | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 2, p. 6, row 56; `ORC-2WUBHCXYPC` |  |
| 1369 | L2 + O2 -> CuO (in oxygen) | L2: O 0.398 | experimental | [1] Hallstedt 1994; _cites Gadalla 1963_ | Table 2, p. 6, row 53; `ORC-U6WDDNE5OI` |  |
| 1363 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.382 | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 2, p. 6, row 42; `ORC-DMMGVFO4IF` |  |
| 1363 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.387 | experimental | [1] Hallstedt 1994; _cites Osterwald 1968_ | Table 2, p. 6, row 39; `ORC-S32TMGTOGC` |  |
| 1363 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.383 | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 40; `ORC-WQNL4XDMJR` |  |
| 1354 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.388 | model | [1] Hallstedt 1994 | Table 2, p. 6, row 44; `ORC-4GQZHANRDK` |  |
| 1353 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.389 | experimental | [1] Hallstedt 1994; _cites Roberts 1921_ [doi](https://doi.org/10.1021/ja01438a009) | Table 2, p. 6, row 37; `ORC-ACIXA4D2PA` |  |
| 1353 | eutectic: L2 -> Cu2O + CuO (eutectic) |  | experimental | [1] Hallstedt 1994; _cites EH 1920_ | Table 2, p. 6, row 36; `ORC-BXXCXZFW7G` |  |
| 1353 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.387 | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 43; `ORC-O2WU72GOKS` |  |
| 1353 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.388 | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 2, p. 6, row 41; `ORC-TQ5DDCZL7S` |  |
| 1348 | eutectic: L2 -> Cu2O + CuO (eutectic) | L2: O 0.39 | experimental | [1] Hallstedt 1994; _cites Vogel 1929_ | Table 2, p. 6, row 38; `ORC-2BX45IZPLJ` |  |
| 1339.6 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.01746 | model | [1] Hallstedt 1994 | Table 2, p. 6, row 10; `ORC-557YSEN6WI` |  |
| 1339.6 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.0174 | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 9; `ORC-GZPD5GUKWR` |  |
| 1339.6 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.0174 | experimental | [1] Hallstedt 1994; _cites ref. 81Tas1_ | Table 2, p. 6, row 7; `ORC-NRNBFOLVX4` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.02 | experimental | [1] Hallstedt 1994; _cites Dejean 1906_ [doi](https://doi.org/10.1051/metal/190603050233) | Table 2, p. 6, row 2; `ORC-7RKVS27PSZ` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.0185 | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 5; `ORC-BONEYXMGOF` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.0173 | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ [doi](https://doi.org/10.1515/ijmr-1968-590711) | Table 2, p. 6, row 4; `ORC-QBYH23OLCH` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.017 | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 2, p. 6, row 8; `ORC-V6ICUB5GBS` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.0154 | experimental | [1] Hallstedt 1994; _cites Heyn 1904_ [doi](https://doi.org/10.1002/zaac.19040390102) | Table 2, p. 6, row 1; `ORC-XRFMQTN4SN` |  |
| 1338 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) | L1: O 0.015 | experimental | [1] Hallstedt 1994; _cites Vogel 1929_ | Table 2, p. 6, row 3; `ORC-XZDQ6ZAMU3` |  |
| 1333 | eutectic: L1 -> Cu (fcc) + Cu2O (eutectic) |  | experimental | [1] Hallstedt 1994; _cites Kemori 1979_ [doi](https://doi.org/10.1016/0021-9614%2879%2990145-9) | Table 2, p. 6, row 6; `ORC-V4MRCYNRSI` |  |
| 1300 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | model | [1] Hallstedt 1994 | Table 2, p. 6, row 65; `ORC-RBB6OGEPK5` |  |
| 1299 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 2, p. 6, row 63; `ORC-4JY2YMRXGZ` |  |
| 1299 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | experimental | [1] Hallstedt 1994; _cites Gadalla 1963_ | Table 2, p. 6, row 61; `ORC-BKBP7UKTZL` |  |
| 1299 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | experimental | [1] Hallstedt 1994; _cites Roberts 1921_ [doi](https://doi.org/10.1021/ja01438a009) | Table 2, p. 6, row 60; `ORC-KAWIJW3ENO` |  |
| 1299 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 64; `ORC-MHDCRUZFUB` |  |
| 1299 | Cu2O + 0.5 O2 -> 2 CuO (in air) |  | experimental | [1] Hallstedt 1994; _cites Eric 1979_ [doi](https://doi.org/10.1007/bf02662558) | Table 2, p. 6, row 62; `ORC-RPRCH4P5IH` |  |

## 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, Cu–O system (27)

| Phase | Compound | Value | T (K) | Class | MP DFT (kJ/mol-atom) | OQMD DFT (kJ/mol-atom) | Source | Location | Quote |
|---|---|---:|---:|---|---:|---:|---|---|---|
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -59.97 kJ/mol-atom | 298.15 | experimental | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Wrhler 1934_ | Table 8, p. 13, row 4; `ORC-UEENQAKLM2.5a9513` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -57.7267 kJ/mol-atom | 298.15 | experimental | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Nufiez 1969_ | Table 8, p. 13, row 10; `ORC-ALFTX6OZRM.279a7f` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -57.4933 kJ/mol-atom | 298.15 | model | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Boud 1991_ | Table 8, p. 13, row 15; `ORC-UDWXTWFN6Y.223526` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -56.9433 kJ/mol-atom | 298.15 | experimental | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Mah 1967_ | Table 8, p. 13, row 8; `ORC-AJGT674S4D.b11196` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -56.9033 kJ/mol-atom | 298.15 | model | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Chase 1985_ | Table 8, p. 13, row 13; `ORC-XCCWO6H7LI.d9fe69` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -56.7633 kJ/mol-atom | 298.15 | experimental | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites Thomsen 1883_ | Table 8, p. 13, row 1; `ORC-T4WZFE2TJJ.eef88f` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -56.7533 kJ/mol-atom | 298.15 | model | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994 | Table 8, p. 13, row 17; `ORC-SNTTKLS5GR.c8b64e` |  |
| Cu2O | [Cu2O](https://data.orchid-project.org/compounds/Cu2O.html) | -54.95 kJ/mol-atom | 293 | experimental | -62.185 (mp-aaaaaanx) | -66.037 (oqmd-643065) | [1] Hallstedt 1994; _cites ref. 34Bil_ | Table 8, p. 13, row 6; `ORC-LGOKEWXJHR.56dd6b` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -80.855 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Nufiez 1969_ | Table 8, p. 13, row 10; `ORC-ALFTX6OZRM.1e7619` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -80.855 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Nufiez 1969_ | Table 8, p. 13, row 12; `ORC-UQ5FDHCSKH` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -80.54 kJ/mol-atom | 295 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites H 1932_ | Table 8, p. 13, row 3; `ORC-J56QLHWYW7` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -78.535 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Nufiez 1969_ | Table 8, p. 13, row 10; `ORC-ALFTX6OZRM.b67909` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -78.535 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Nufiez 1969_ | Table 8, p. 13, row 11; `ORC-I5UR2MQHUO` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -78.03 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Chase 1985_ | Table 8, p. 13, row 14; `ORC-C7MXYNKNHW` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -78.03 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Chase 1985_ | Table 8, p. 13, row 13; `ORC-XCCWO6H7LI.fa10e4` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.885 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Mah 1967_ | Table 8, p. 13, row 8; `ORC-AJGT674S4D.aad2e0` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.885 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Mah 1967_ | Table 8, p. 13, row 9; `ORC-QQXJ6OCZ6G` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.74 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Thomsen 1883_ | Table 8, p. 13, row 2; `ORC-GMNQNEO2HB` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.74 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Thomsen 1883_ | Table 8, p. 13, row 1; `ORC-T4WZFE2TJJ.006290` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.595 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994 | Table 8, p. 13, row 18; `ORC-QZDH5SGEEG` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.595 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994 | Table 8, p. 13, row 17; `ORC-SNTTKLS5GR.ce4045` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.015 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Boud 1991_ | Table 8, p. 13, row 16; `ORC-LAWLJGIQGF` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -77.015 kJ/mol-atom | 298.15 | model | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Boud 1991_ | Table 8, p. 13, row 15; `ORC-UDWXTWFN6Y.049c73` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -76.15 kJ/mol-atom | 293 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites ref. 34Bil_ | Table 8, p. 13, row 7; `ORC-4TQ3RYV4BP` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -76.15 kJ/mol-atom | 293 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites ref. 34Bil_ | Table 8, p. 13, row 6; `ORC-LGOKEWXJHR.e36160` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -69.08 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Wrhler 1934_ | Table 8, p. 13, row 5; `ORC-PYVAEHKD5K` |  |
| CuO | [CuO](https://data.orchid-project.org/compounds/CuO.html) | -69.08 kJ/mol-atom | 298.15 | experimental | -90.966 (mp-aaaaacnc) | -80.231 (oqmd-1343583) | [1] Hallstedt 1994; _cites Wrhler 1934_ | Table 8, p. 13, row 4; `ORC-UEENQAKLM2.d6b8e9` |  |

## Other properties

### Phase transition (13)

Table: Phase transition, Cu–O system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Phase transition | 230 K | 230 | magnetic | experimental | [1] Hallstedt 1994; _cites O'Keeffe 1962_ | p. 4; `ORC-TBOXSWZ4NZ` | “There is a paramagnetic-antiferromagnetic transition in CuO with a N4el temperature at 230 K \[62Oke, 88See\].” |
| Phase transition | 230 K | 230 | magnetic | experimental | [2] Schramm 2005; _cites OKeeffe 1962_ | p. 4; `ORC-XE4LLV4TYU` | “The paramagnetic-antiferromagnetic transition\[30,31\] in CuO with a Néel temperature at 230 K is far below the modeled temperature range, and was not considered in this work.” |
| Phase transition | 1483 K | 1483 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Slade 1912_ [doi](https://doi.org/10.1098/rspa.1912.0107) | Table 2, p. 6, row 25; `ORC-CY5VTBVYMJ` |  |
| Phase transition | 1498 K | 1498 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ [doi](https://doi.org/10.1515/ijmr-1968-590711) | Table 2, p. 6, row 29; `ORC-YOY6ZWUXMI` |  |
| Phase transition | 1499 K | 1499 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Kayahara 1981_ [doi](https://doi.org/10.2320/jinstmet1952.42.5_527) | Table 2, p. 6, row 31; `ORC-CZGWZ35KZM` |  |
| Phase transition | 1500 K | 1500 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Taskinen 1984_ | Table 2, p. 6, row 32; `ORC-4VR5577JMC` |  |
| Phase transition | 1500 K | 1500 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 2, p. 6, row 30; `ORC-UTXRLHY3L7` |  |
| Phase transition | 1500 K | 1500 | congruent melting: L2 -> Cu2O (congruent melting point) | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 2, p. 6, row 33; `ORC-Y5ERKINEXI` |  |
| Phase transition | 1501 K | 1501 | congruent melting: L2 -> Cu2O (congruent melting point) | model | [1] Hallstedt 1994 | Table 2, p. 6, row 35; `ORC-ULFB5Q3U4S` |  |
| Phase transition | 1502 K | 1502 | congruent melting: L2 -> Cu2O (congruent melting point) | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 2, p. 6, row 34; `ORC-NFDRS4O2PZ` |  |
| Phase transition | 1502 K | 1502 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Osterwald 1968_ | Table 2, p. 6, row 28; `ORC-YNHZJHU6TO` |  |
| Phase transition | 1508 K | 1508 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Roberts 1921_ [doi](https://doi.org/10.1021/ja01438a009) | Table 2, p. 6, row 26; `ORC-OYIZ237L6E` |  |
| Phase transition | 1515 K | 1515 | congruent melting: L2 -> Cu2O (congruent melting point) | experimental | [1] Hallstedt 1994; _cites Mah 1967_ | Table 2, p. 6, row 27; `ORC-4XS3GR7B33` |  |

### Formation (12)

Table: Formation, Cu–O system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Gibbs energy of formation; _printed: ΔfG(Cu2O)_ | -145.8 kJ/mol (basis unstated) | 290 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Allmand 1910_ [doi](https://doi.org/10.1039/ct9109700603) | Table 11, p. 13, row 11; `ORC-7Z7O6AAGAF` |  |
| Gibbs energy of formation; _printed: ΔfG(Cu2O)_ | -148.19 kJ/mol (basis unstated) | 291 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 11All_ | Table 11, p. 13, row 12; `ORC-VPZADYPWZ4` |  |
| Gibbs energy of formation; _printed: ΔfG(Cu2O)_ | -145.07 kJ/mol (basis unstated) | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Maier 1929_ [doi](https://doi.org/10.1021/ja01376a024) | Table 11, p. 13, row 4; `ORC-GNTGZPTRWU.76e076` |  |
| Gibbs energy of formation; _printed: ΔfG(Cu2O)_ | -147.56 kJ/mol (basis unstated) | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 11, p. 13, row 10; `ORC-JFNBHZ6QIT.9d7309` |  |
| Gibbs energy of formation; _printed: ΔfG(Cu2O)_ | -147.89 kJ/mol (basis unstated) | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 11, p. 13, row 9; `ORC-PYTD2C6HQG.cc2677` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -126.51 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Feitknecht 1944_ [doi](https://doi.org/10.1002/hlca.19440270195) | Table 11, p. 13, row 5; `ORC-6UDG3C7ZKD` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -128.87 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Maier 1929_ [doi](https://doi.org/10.1021/ja01376a024) | Table 11, p. 13, row 4; `ORC-GNTGZPTRWU.08659c` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -126.51 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Barton 1960_ | Table 11, p. 13, row 7; `ORC-HVU354ELUU` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -127.58 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994 | Table 11, p. 13, row 10; `ORC-JFNBHZ6QIT.b0a643` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -124.56 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Nasanen 1949_ [doi](https://doi.org/10.1021/ja01174a027) | Table 11, p. 13, row 6; `ORC-KG4CA5XGAC` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -128.24 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Schindler 1965_ [doi](https://doi.org/10.1002/hlca.19650480528) | Table 11, p. 13, row 8; `ORC-LD5YGNOXIK` |  |
| Gibbs energy of formation; _printed: ΔfG(CuO)_ | -128.29 kJ/mol (basis unstated) | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 11, p. 13, row 9; `ORC-PYTD2C6HQG.5a5daa` |  |

### Heat capacity / entropy / enthalpy (37)

Table: Heat capacity / entropy / enthalpy, Cu–O system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Entropy; _printed: S(Cu2O)_ | 93.87 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Hu 1951_ [doi](https://doi.org/10.1021/ja01154a017) | Table 9, p. 13, row 3; `ORC-5ZECNSZV3Z` |  |
| Entropy; _printed: S(Cu2O)_ | 90.68 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 9, p. 13, row 9; `ORC-EV7BCBJBQP.e517a4` |  |
| Entropy; _printed: S(Cu2O)_ | 92.36 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 9, p. 13, row 7; `ORC-NSS6F7CT4V.ad4587` |  |
| Entropy; _printed: S(Cu2O)_ | 92.68 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 9, p. 13, row 11; `ORC-OECWWZSYJ2.57737a` |  |
| Entropy; _printed: S(Cu2O)_ | 90.79 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 29Mil_ | Table 9, p. 13, row 1; `ORC-ULKKEJRK5I.617b8a` |  |
| Entropy; _printed: S(Cu2O)_ | 92.38 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Mah 1967_ | Table 9, p. 13, row 6; `ORC-X7SIJDEEVF` |  |
| Entropy; _printed: S(Cu2O)_ | 93.14 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Gregor 1962_ [doi](https://doi.org/10.1021/j100815a019) | Table 9, p. 13, row 5; `ORC-ZAAFXV7ZVJ` |  |
| Entropy; _printed: S(CuO)_ | 40.79 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites ref. 29Mil_ | Table 9, p. 13, row 2; `ORC-44KDA2LXLC` |  |
| Entropy; _printed: S(CuO)_ | 43.06 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994 | Table 9, p. 13, row 12; `ORC-7HWRPP6NOY` |  |
| Entropy; _printed: S_ | 43.69 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: Cu 0.5, O 0.5_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 9, p. 13, row 9; `ORC-EV7BCBJBQP.1daf0f` |  |
| Entropy; _printed: S(CuO)_ | 42.59 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 9, p. 13, row 8; `ORC-GQYULRE3HZ` |  |
| Entropy; _printed: S(CuO)_ | 43.69 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 9, p. 13, row 10; `ORC-HA2ECPLO6G` |  |
| Entropy; _printed: S(CuO)_ | 42.63 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Hu 1953_ [doi](https://doi.org/10.1021/ja01106a056) | Table 9, p. 13, row 4; `ORC-KED2WBNEVN` |  |
| Entropy; _printed: S_ | 42.59 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: Cu 0.5, O 0.5_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 9, p. 13, row 7; `ORC-NSS6F7CT4V.cb8faf` |  |
| Entropy; _printed: S_ | 43.06 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: Cu 0.5, O 0.5_ | model | [1] Hallstedt 1994 | Table 9, p. 13, row 11; `ORC-OECWWZSYJ2.e9e55e` |  |
| Entropy; _printed: S_ | 40.79 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: Cu 0.5, O 0.5_ | experimental | [1] Hallstedt 1994; _cites ref. 29Mil_ | Table 9, p. 13, row 1; `ORC-ULKKEJRK5I.fb9d28` |  |
| Heat capacity; _printed: Cp (liquid)_ | 87.8 J/mol (basis unstated)/K |  | liquid Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 5, p. 10, row 4; `ORC-4K6HSI725U` |  |
| Heat capacity; _printed: Cp (liquid)_ | 99.9 J/mol (basis unstated)/K |  | liquid Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Mah 1967_ | Table 5, p. 10, row 1; `ORC-DPGFHUW2B5` |  |
| Heat capacity; _printed: Cp (liquid)_ | 81.4 J/mol (basis unstated)/K |  | liquid Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 5, p. 10, row 3; `ORC-KFHM34OBGB` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 64 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Neumann 1831_ | Table 10, p. 13, row 1; `ORC-52YBVQEJ6S.35c7a0` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 63.64 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Hu 1951_ [doi](https://doi.org/10.1021/ja01154a017) | Table 10, p. 13, row 7; `ORC-5FMTW3ZRLG` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 66.5 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kopp 1865_ [doi](https://doi.org/10.1098/rstl.1865.0003) | Table 10, p. 13, row 3; `ORC-6REBURDRI3.5ad757` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 61.84 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 29Mil_ | Table 10, p. 13, row 6; `ORC-7BXDEZZWGO.c8a142` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 62.59 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Mah 1967_ | Table 10, p. 13, row 9; `ORC-K3QUAAGRWH` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 62.47 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 10, p. 13, row 12; `ORC-KFKTYIZNKX.365ccc` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 68.66 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Magnus 1911_ | Table 10, p. 13, row 4; `ORC-OUBWHI5MAO` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 62.54 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 10, p. 13, row 10; `ORC-RXH5DCZFWK.29260c` |  |
| Heat capacity; _printed: Cp(Cu2O)_ | 62.7 J/mol (basis unstated)/K | 298.15 | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 10, p. 13, row 11; `ORC-XDRQ5IH6ZL.387fdd` |  |
| Heat capacity; _printed: Cp(CuO)_ | 45.6 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Neumann 1831_ | Table 10, p. 13, row 1; `ORC-52YBVQEJ6S.24ab3e` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.7 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Kopp 1865_ [doi](https://doi.org/10.1098/rstl.1865.0003) | Table 10, p. 13, row 3; `ORC-6REBURDRI3.c69508` |  |
| Heat capacity; _printed: Cp(CuO)_ | 47.3 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Regnault 1841_ | Table 10, p. 13, row 2; `ORC-75PIHBMOMD` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.59 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites ref. 29Mil_ | Table 10, p. 13, row 6; `ORC-7BXDEZZWGO.059d70` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.3 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Hu 1953_ [doi](https://doi.org/10.1021/ja01106a056) | Table 10, p. 13, row 8; `ORC-D6Q2MMFB7G` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.26 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994 | Table 10, p. 13, row 12; `ORC-KFKTYIZNKX.12dc45` |  |
| Heat capacity; _printed: Cp(CuO)_ | 43.5 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | experimental | [1] Hallstedt 1994; _cites Russell 1912_ | Table 10, p. 13, row 5; `ORC-NLSRSMREX3` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.25 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 10, p. 13, row 10; `ORC-RXH5DCZFWK.c7b301` |  |
| Heat capacity; _printed: Cp(CuO)_ | 42.29 J/mol (basis unstated)/K | 298.15 | CuO; _alloy: O 0.5_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 10, p. 13, row 11; `ORC-XDRQ5IH6ZL.47d4e4` |  |

### Activity / EMF / Gibbs energy (38)

Table: Activity / EMF / Gibbs energy, Cu–O system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| Gibbs energy; _printed: ΔG0_ | -78380 J/mol |  | liquid | experimental | [1] Hallstedt 1994; _cites E Puchi 1979_ | Table 3, p. 10, row 1; `ORC-QQLVQW76AV.a2e7bf` |  |
| Gibbs energy; _printed: ΔG0_ | -77920 J/mol |  | liquid | experimental | [1] Hallstedt 1994; _cites E Puchi 1979_ | Table 3, p. 10, row 1; `ORC-QQLVQW76AV.ed7e5e` |  |
| Gibbs energy; _printed: ΔG0_ | -76200 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Diaz 1967_ | Table 3, p. 9, row 10; `ORC-4UXMCVB6KX.086889` |  |
| Gibbs energy; _printed: ΔG0_ | -75820 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Diaz 1967_ | Table 3, p. 9, row 10; `ORC-4UXMCVB6KX.bb8f7e` |  |
| Gibbs energy; _printed: ΔG0_ | -79080 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Tankins 1965_ | Table 3, p. 9, row 6; `ORC-74F5ZZCFJB.196655` |  |
| Gibbs energy; _printed: ΔG0_ | -78150 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Tankins 1965_ | Table 3, p. 9, row 6; `ORC-74F5ZZCFJB.5845f3` |  |
| Gibbs energy; _printed: ΔG0_ | -75400 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Fitzner 1979_ [doi](https://doi.org/10.1179/030716979803276255) | Table 3, p. 9, row 37; `ORC-7U23KLOAO4.153a7e` |  |
| Gibbs energy; _printed: ΔG0_ | -73550 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Fitzner 1979_ [doi](https://doi.org/10.1179/030716979803276255) | Table 3, p. 9, row 37; `ORC-7U23KLOAO4.707e20` |  |
| Gibbs energy; _printed: ΔG0_ | -76620 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Hendry 1974_ | Table 3, p. 9, row 30; `ORC-BQUFL322DG.a469dd` |  |
| Gibbs energy; _printed: ΔG0_ | -80940 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Hendry 1974_ | Table 3, p. 9, row 30; `ORC-BQUFL322DG.e5f110` |  |
| Gibbs energy; _printed: ΔG0_ | -77920 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites E Puchi 1979_ | Table 3, p. 9, row 39; `ORC-DPSOLMSOUE.ee4134` |  |
| Gibbs energy; _printed: ΔG0_ | -78380 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites E Puchi 1979_ | Table 3, p. 9, row 39; `ORC-DPSOLMSOUE.ee612f` |  |
| Gibbs energy; _printed: ΔG0_ | -85530 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites M 1967_ | Table 3, p. 9, row 11; `ORC-HLI7SHVJ2U.8c4270` |  |
| Gibbs energy; _printed: ΔG0_ | -85690 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites M 1967_ | Table 3, p. 9, row 11; `ORC-HLI7SHVJ2U.ef0933` |  |
| Gibbs energy; _printed: ΔG0_ | -76130 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites ref. 71Jac_ | Table 3, p. 9, row 23; `ORC-NMBWFWIITG.23ef9a` |  |
| Gibbs energy; _printed: ΔG0_ | -75000 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites ref. 71Jac_ | Table 3, p. 9, row 23; `ORC-NMBWFWIITG.7a1eaa` |  |
| Gibbs energy; _printed: ΔG0_ | -75960 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Wilder 1966_ | Table 3, p. 9, row 9; `ORC-S3NQ2UDDAZ.073cbf` |  |
| Gibbs energy; _printed: ΔG0_ | -76900 J/mol |  | liquid Cu | experimental | [1] Hallstedt 1994; _cites Wilder 1966_ | Table 3, p. 9, row 9; `ORC-S3NQ2UDDAZ.d763d8` |  |
| Gibbs energy; _printed: ΔG(Cu2O/CuO)_ | -110.21 kJ/mol | 290 | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 10All_ | Table 11, p. 13, row 2; `ORC-OF7WFZ4FIS` |  |
| Gibbs energy; _printed: ΔG(Cu2O/CuO)_ | -112.67 kJ/mol | 298.15 | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Maier 1929_ [doi](https://doi.org/10.1021/ja01376a024) | Table 11, p. 13, row 4; `ORC-GNTGZPTRWU.544bc1` |  |
| Gibbs energy; _printed: ΔG(Cu2O/CuO)_ | -107.6 kJ/mol | 298.15 | UNKNOWN | model | [1] Hallstedt 1994 | Table 11, p. 13, row 10; `ORC-JFNBHZ6QIT.c5018b` |  |
| Gibbs energy; _printed: ΔG(Cu2O/CuO)_ | -108.7 kJ/mol | 298.15 | UNKNOWN | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 11, p. 13, row 9; `ORC-PYTD2C6HQG.620249` |  |
| Gibbs energy; _printed: ΔG0_ | -76590 J/mol | 1373 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Fitzner 1978_ | Table 3, p. 9, row 35; `ORC-3EFJSN4QOF.75bda9` |  |
| Gibbs energy; _printed: ΔG0_ | -76650 J/mol | 1408 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Nanda 1970_ [doi](https://doi.org/10.1007/bf02900236) | Table 3, p. 9, row 20; `ORC-XZ62TAIPXP.a0c217` |  |
| Gibbs energy; _printed: ΔG0_ | -76660 J/mol | 1418 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Rickert 1966_ [doi](https://doi.org/10.1016/0013-4686%2866%2985009-0) | Table 3, p. 9, row 8; `ORC-7BFVWN7U2H.749df8` |  |
| Gibbs energy; _printed: ΔG0_ | -79570 J/mol | 1423 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Moser 1975_ | Table 3, p. 9, row 33; `ORC-56337Y7FXN.b04159` |  |
| Gibbs energy; _printed: ΔG0_ | -75460 J/mol | 1423 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Fischer 1970_ [doi](https://doi.org/10.1002/srin.197003613) | Table 3, p. 9, row 19; `ORC-L5X7GLZTTJ.bc881e` |  |
| Gibbs energy; _printed: ΔG0_ | -73640 J/mol | 1423 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Janke 1975_ | Table 3, p. 9, row 32; `ORC-XAKXVF5BJV.52042c` |  |
| Gibbs energy; _printed: ΔG0_ | -77920 J/mol | 1423 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Pluschkell 1965_ | Table 3, p. 9, row 5; `ORC-XB4JYCNZTJ.7c6880` |  |
| Gibbs energy; _printed: ΔG0_ | -74600 J/mol | 1473 | liquid | experimental | [1] Hallstedt 1994; _cites Sudavtsova 1979_ | Table 3, p. 10, row 2; `ORC-2ZXJFN7YTS.4c043c` |  |
| Gibbs energy; _printed: ΔG0_ | -75400 J/mol | 1473 | liquid | experimental | [1] Hallstedt 1994; _cites ref. 83Aru_ | Table 3, p. 10, row 8; `ORC-O76BQIVPLG.fd30ff` |  |
| Gibbs energy; _printed: ΔG0_ | -75940 J/mol | 1473 | liquid Cu | experimental | [1] Hallstedt 1994; _cites ref. 69Blo_ | Table 3, p. 9, row 16; `ORC-F4TKBFITLY.603a92` |  |
| Gibbs energy; _printed: ΔG0_ | -76360 J/mol | 1473 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Staffansson 1974_ | Table 3, p. 9, row 31; `ORC-JBEB4TYVMC.7b4c4d` |  |
| Gibbs energy; _printed: ΔG0_ | -75400 J/mol | 1473 | liquid Cu | experimental | [1] Hallstedt 1994; _cites ref. 83Aru_ | Table 3, p. 9, row 46; `ORC-MZOM5VWVM2.e793ec` |  |
| Gibbs energy; _printed: ΔG0_ | -74600 J/mol | 1473 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Sudavtsova 1979_ | Table 3, p. 9, row 40; `ORC-Y2SS7PSHJF.0bd5c5` |  |
| Gibbs energy; _printed: ΔG0_ | -75240 J/mol | 1573 | liquid | experimental | [1] Hallstedt 1994; _cites Kemori 1980_ [doi](https://doi.org/10.2320/matertrans1960.21.275) | Table 3, p. 10, row 4; `ORC-XM4GY2U7ZY.31e7e4` |  |
| Gibbs energy; _printed: ΔG0_ | -75240 J/mol | 1573 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Kemori 1980_ [doi](https://doi.org/10.2320/matertrans1960.21.275) | Table 3, p. 9, row 42; `ORC-2PC2ERV2SY.2c322a` |  |
| Gibbs energy; _printed: ΔG0_ | -75160 J/mol | 1873 | liquid Cu | experimental | [1] Hallstedt 1994; _cites Fischer 1971_ | Table 3, p. 9, row 22; `ORC-2GMNJXTTAO.d63f22` |  |

### Model expression (174)

Table: Model expression, Cu–O system

| Property | Value | T (K) | Phases / composition | Class | Source | Location | Quote |
|---|---:|---:|---|---|---|---|---|
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 69.29 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Matsushita 1964_ | Table 6, p. 11, row 6; `ORC-3JMBL4OVFH.075b76` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -166400 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Matsushita 1964_ | Table 6, p. 11, row 6; `ORC-3JMBL4OVFH.0fd2fb` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 72.66 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Sellars 1966_ | Table 6, p. 11, row 9; `ORC-4AMCJQ7AQQ.620ce1` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -168620 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Sellars 1966_ | Table 6, p. 11, row 9; `ORC-4AMCJQ7AQQ.927f0d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -161830 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Hammer 1984_ | Table 6, p. 11, row 24; `ORC-4VGKGMYU3L.644c0b` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 64.82 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Hammer 1984_ | Table 6, p. 11, row 24; `ORC-4VGKGMYU3L.e91a07` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 72.2 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites EE 1967_ | Table 6, p. 11, row 11; `ORC-5RGTQRFCPL.bdc86d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167610 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites EE 1967_ | Table 6, p. 11, row 11; `ORC-5RGTQRFCPL.f8a390` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -174140 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 86Hol_ | Table 6, p. 11, row 27; `ORC-6NIMPI3DXL.1f6cb9` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 124.91 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 86Hol_ | Table 6, p. 11, row 27; `ORC-6NIMPI3DXL.b496c8` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T lnT)_ | -6.67 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 86Hol_ | Table 6, p. 11, row 27; `ORC-6NIMPI3DXL.c49dad` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 74 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Peters 1958_ [doi](https://doi.org/10.1007/bf00639610) | Table 6, p. 11, row 5; `ORC-6SF5DKLPBG.50d4bf` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167330 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Peters 1958_ [doi](https://doi.org/10.1007/bf00639610) | Table 6, p. 11, row 5; `ORC-6SF5DKLPBG.ccc5e6` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 119.88 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 89Hol_ | Table 6, p. 11, row 29; `ORC-AHSR7GAB4B.414596` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -173240 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 89Hol_ | Table 6, p. 11, row 29; `ORC-AHSR7GAB4B.61eb68` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T lnT)_ | -6.09 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 89Hol_ | Table 6, p. 11, row 29; `ORC-AHSR7GAB4B.aa589d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -177280 J/mol |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 6, p. 11, row 33; `ORC-CENDH2PUUM.302970` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 134.92 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 6, p. 11, row 33; `ORC-CENDH2PUUM.4df658` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 69.57 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Sugimoto 1980_ [doi](https://doi.org/10.2320/jinstmet1952.44.6_644) | Table 6, p. 11, row 23; `ORC-DMNWWVHKPM.b30fe8` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -164300 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Sugimoto 1980_ [doi](https://doi.org/10.2320/jinstmet1952.44.6_644) | Table 6, p. 11, row 23; `ORC-DMNWWVHKPM.f3c5a2` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -173730 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Chiche 1951_ | Table 6, p. 11, row 2; `ORC-DRKCT4WETM.1aeb1d` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 96.45 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Chiche 1951_ | Table 6, p. 11, row 2; `ORC-DRKCT4WETM.c8b106` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -166760 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 6, p. 11, row 30; `ORC-EWT5CGDIZ7.086530` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.99 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 6, p. 11, row 30; `ORC-EWT5CGDIZ7.a06536` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 70.46 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Fischer 1970_ [doi](https://doi.org/10.1002/srin.197003613) | Table 6, p. 11, row 19; `ORC-FRBIGFNSVM.348f05` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -165730 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Fischer 1970_ [doi](https://doi.org/10.1002/srin.197003613) | Table 6, p. 11, row 19; `ORC-FRBIGFNSVM.921df3` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -173850 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites St 1988_ | Table 6, p. 11, row 28; `ORC-FVAJVTZKWQ.6a42a9` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 122.99 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites St 1988_ | Table 6, p. 11, row 28; `ORC-FVAJVTZKWQ.e40317` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 74.61 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kiukkola 1958_ | Table 6, p. 11, row 3; `ORC-G3IUQGJS3L.1771f4` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -171440 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kiukkola 1958_ | Table 6, p. 11, row 3; `ORC-G3IUQGJS3L.205a9c` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167390 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Moriyama 1969_ | Table 6, p. 11, row 16; `ORC-G7EJSAORER.0fcc95` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.99 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Moriyama 1969_ | Table 6, p. 11, row 16; `ORC-G7EJSAORER.b050f1` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 72.66 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Treadwell 1916_ | Table 6, p. 11, row 1; `ORC-GR5NIJXTBL.3f8cdc` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -162580 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Treadwell 1916_ | Table 6, p. 11, row 1; `ORC-GR5NIJXTBL.a95bc3` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -100340 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 58Hil_ | Table 6, p. 11, row 4; `ORC-IV5ZCC2YHR` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 93.99 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Barbi 1970_ | Table 6, p. 11, row 17; `ORC-IW22ENBQDY.2af2ae` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -170220 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Barbi 1970_ | Table 6, p. 11, row 17; `ORC-IW22ENBQDY.43574e` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -174010 J/mol |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 6, p. 11, row 34; `ORC-IYIRG5ICJS.10893f` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 125.48 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994 | Table 6, p. 11, row 34; `ORC-IYIRG5ICJS.1956c0` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 70.93 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Taskinen 1981_ | Table 6, p. 11, row 25; `ORC-JXXN37MYUS.96446e` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -166300 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Taskinen 1981_ | Table 6, p. 11, row 25; `ORC-JXXN37MYUS.f3da47` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -165490 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kemori 1979_ [doi](https://doi.org/10.1016/0021-9614%2879%2990145-9) | Table 6, p. 11, row 22; `ORC-KA27GTJUEE.6e9708` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 69.87 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kemori 1979_ [doi](https://doi.org/10.1016/0021-9614%2879%2990145-9) | Table 6, p. 11, row 22; `ORC-KA27GTJUEE.a39f68` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -166670 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Mallika 1985_ [doi](https://doi.org/10.1016/0022-5088%2885%2990079-7) | Table 6, p. 11, row 26; `ORC-LD6ZCKZCZH.2ac607` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 72.45 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Mallika 1985_ [doi](https://doi.org/10.1016/0022-5088%2885%2990079-7) | Table 6, p. 11, row 26; `ORC-LD6ZCKZCZH.77dd87` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.56 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites EE 1967_ | Table 6, p. 11, row 10; `ORC-LW2FEBLTRI.4614d8` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167170 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites EE 1967_ | Table 6, p. 11, row 10; `ORC-LW2FEBLTRI.fb898a` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -173570 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ | Table 6, p. 11, row 13; `ORC-OOXHI72C6C.94d1b5` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 76.99 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ | Table 6, p. 11, row 13; `ORC-OOXHI72C6C.b0c833` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 47.7 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kodera 1968_ [doi](https://doi.org/10.1246/bcsj.41.1039) | Table 6, p. 11, row 14; `ORC-Q3PXQF2F5B.2d741c` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -134720 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kodera 1968_ [doi](https://doi.org/10.1246/bcsj.41.1039) | Table 6, p. 11, row 14; `ORC-Q3PXQF2F5B.3b1a8b` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -174080 J/mol |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 6, p. 11, row 32; `ORC-QWO43Y5GKZ.1ce578` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 122.9 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 6, p. 11, row 32; `ORC-QWO43Y5GKZ.c3e51d` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 72.63 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Yu 1965_ | Table 6, p. 11, row 8; `ORC-RMAAHCQQH7.00a324` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -168850 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Yu 1965_ | Table 6, p. 11, row 8; `ORC-RMAAHCQQH7.7656e0` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -166650 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Bugden 1970_ | Table 6, p. 11, row 18; `ORC-RUHFVNBSIM.291e13` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.22 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Bugden 1970_ | Table 6, p. 11, row 18; `ORC-RUHFVNBSIM.98016d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167640 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Charette 1968_ [doi](https://doi.org/10.1149/1.2411434) | Table 6, p. 11, row 12; `ORC-SBTFE54NSG.a6f956` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.7 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Charette 1968_ [doi](https://doi.org/10.1149/1.2411434) | Table 6, p. 11, row 12; `ORC-SBTFE54NSG.cfbc0f` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167360 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Steele 1965_ | Table 6, p. 11, row 7; `ORC-TJM7VWKP5Y.9dbeac` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.94 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Steele 1965_ | Table 6, p. 11, row 7; `ORC-TJM7VWKP5Y.f323a3` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -167650 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 71Slo_ | Table 6, p. 11, row 20; `ORC-ULOJOE4C4L.a46381` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 71.47 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 71Slo_ | Table 6, p. 11, row 20; `ORC-ULOJOE4C4L.e0055d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -148530 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kazenas 1969_ | Table 6, p. 11, row 15; `ORC-USOYPB2BG6.b66f14` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 59.58 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites Kazenas 1969_ | Table 6, p. 11, row 15; `ORC-USOYPB2BG6.eab528` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 69.88 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 75Mos1_ | Table 6, p. 11, row 21; `ORC-XDQRT5TIP6.24e69c` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -165080 J/mol |  | Cu2O; _alloy: O 0.333333_ | experimental | [1] Hallstedt 1994; _cites ref. 75Mos1_ | Table 6, p. 11, row 21; `ORC-XDQRT5TIP6.34ff91` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term A)_ | -169100 J/mol |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 6, p. 11, row 31; `ORC-XPOZC73DZ5.5149c5` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 73.33 J/mol/K |  | Cu2O; _alloy: O 0.333333_ | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 6, p. 11, row 31; `ORC-XPOZC73DZ5.c852fb` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -121760 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites EH 1920_ | Table 7, p. 12, row 3; `ORC-2I43UH2F3Z.22ae3d` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 87.22 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites EH 1920_ | Table 7, p. 12, row 3; `ORC-2I43UH2F3Z.52521c` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -126880 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Gadalla 1963_ | Table 7, p. 12, row 6; `ORC-3BYJUDMXIT.915cd6` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 90.75 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Gadalla 1963_ | Table 7, p. 12, row 6; `ORC-3BYJUDMXIT.bc0714` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 187.96 unknown |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 7, p. 12, row 23; `ORC-3LPDSV6S5E.0f4244` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -144900 J/mol |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Chase 1985_ | Table 7, p. 12, row 23; `ORC-3LPDSV6S5E.37483c` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 177.56 unknown |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 7, p. 12, row 24; `ORC-3QUA646NFY.2af8cd` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -138180 J/mol |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Boud 1991_ | Table 7, p. 12, row 24; `ORC-3QUA646NFY.ee57e6` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -118520 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Foote 1908_ [doi](https://doi.org/10.1021/ja01951a002) | Table 7, p. 12, row 1; `ORC-4A5RRZCZFP.47f6a9` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 84.72 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Foote 1908_ [doi](https://doi.org/10.1021/ja01951a002) | Table 7, p. 12, row 1; `ORC-4A5RRZCZFP.a24531` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -125240 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 7, p. 12, row 19; `ORC-6TGU6LZEPF.0a6b99` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 89.84 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Boud 1991_ | Table 7, p. 12, row 19; `ORC-6TGU6LZEPF.faa21e` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -131110 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 7, p. 12, row 20; `ORC-6VJFZQRMBG.b22c42` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 94.36 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 7, p. 12, row 20; `ORC-6VJFZQRMBG.dbf8b4` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 93.22 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Kodera 1968_ [doi](https://doi.org/10.1246/bcsj.41.1039) | Table 7, p. 12, row 12; `ORC-CFURCZMWND.274952` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -135560 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Kodera 1968_ [doi](https://doi.org/10.1246/bcsj.41.1039) | Table 7, p. 12, row 12; `ORC-CFURCZMWND.f15339` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -130450 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 75Jac_ | Table 7, p. 12, row 17; `ORC-DHJ4CYDW53.28f5ff` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 93.98 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 75Jac_ | Table 7, p. 12, row 17; `ORC-DHJ4CYDW53.734e37` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -125350 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 71Slo_ | Table 7, p. 12, row 16; `ORC-DJRIKTS2PY.2cc5be` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 88.84 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 71Slo_ | Table 7, p. 12, row 16; `ORC-DJRIKTS2PY.88f2e5` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 94.58 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Chiche 1951_ | Table 7, p. 12, row 4; `ORC-DMKJ45C3L3.8c5ce6` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -130920 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Chiche 1951_ | Table 7, p. 12, row 4; `ORC-DMKJ45C3L3.a3db03` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -164810 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Matsushita 1964_ | Table 7, p. 12, row 7; `ORC-G5RXPA5OOE.34120b` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 125.18 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Matsushita 1964_ | Table 7, p. 12, row 7; `ORC-G5RXPA5OOE.8855ef` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 185.32 unknown |  | UNKNOWN | model | [1] Hallstedt 1994 | Table 7, p. 12, row 25; `ORC-IBGR2MCODD.1ae6d2` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -143380 J/mol |  | UNKNOWN | model | [1] Hallstedt 1994 | Table 7, p. 12, row 25; `ORC-IBGR2MCODD.7d6a95` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -126930 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Assayag 1955_ | Table 7, p. 12, row 5; `ORC-JBGVMASELP.547a6b` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 90.89 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Assayag 1955_ | Table 7, p. 12, row 5; `ORC-JBGVMASELP.81b053` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 95.15 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Charette 1968_ [doi](https://doi.org/10.1149/1.2411434) | Table 7, p. 12, row 11; `ORC-KPNFBU7H47.91ac50` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -132040 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Charette 1968_ [doi](https://doi.org/10.1149/1.2411434) | Table 7, p. 12, row 11; `ORC-KPNFBU7H47.e9257f` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -118510 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Kazenas 1969_ | Table 7, p. 12, row 14; `ORC-OUZ3PV7RKV.9ea6f8` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 76.61 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Kazenas 1969_ | Table 7, p. 12, row 14; `ORC-OUZ3PV7RKV.df97a8` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -142220 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Barbi 1970_ | Table 7, p. 12, row 15; `ORC-QVLVG54NQG.940bde` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 173.54 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Barbi 1970_ | Table 7, p. 12, row 15; `ORC-QVLVG54NQG.c2579a` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -130950 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Bidwell 1967_ [doi](https://doi.org/10.1149/1.2426501) | Table 7, p. 12, row 9; `ORC-RE2IACCZEJ.5d3371` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 94.38 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Bidwell 1967_ [doi](https://doi.org/10.1149/1.2426501) | Table 7, p. 12, row 9; `ORC-RE2IACCZEJ.7cad7e` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 96.15 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites St 1988_ | Table 7, p. 12, row 18; `ORC-RTJG7AX7DI.6b6e47` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -134080 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites St 1988_ | Table 7, p. 12, row 18; `ORC-RTJG7AX7DI.efc531` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 89.38 unknown |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 7, p. 12, row 22; `ORC-TFRANQQETA.06fa30` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -128100 J/mol |  | UNKNOWN | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 7, p. 12, row 22; `ORC-TFRANQQETA.0f5a4a` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 93.59 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Hochgeschwender 1968_ | Table 7, p. 12, row 10; `ORC-UBDYG5KDMA.5de9eb` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -129700 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Hochgeschwender 1968_ | Table 7, p. 12, row 10; `ORC-UBDYG5KDMA.cd959f` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -10950 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites ref. 64Sch_ | Table 7, p. 12, row 8; `ORC-XF2SO5UJWI` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -134230 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Treadwell 1916_ | Table 7, p. 12, row 2; `ORC-Y6OVFQXYPL.1387f4` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 98.84 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Treadwell 1916_ | Table 7, p. 12, row 2; `ORC-Y6OVFQXYPL.a002c4` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -132410 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 7, p. 12, row 21; `ORC-Z2P7ECAUYP.d9b89d` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 96.63 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Suzuki 1992_ [doi](https://doi.org/10.1111/j.1151-2916.1992.tb05513.x) | Table 7, p. 12, row 21; `ORC-Z2P7ECAUYP.e609f9` |  |
| gibbs energy expression term; _printed: ΔG0 coefficient of T_ | 96.42 unknown |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Rigdon 1969_ | Table 7, p. 12, row 13; `ORC-ZPC6I3K6OQ.295f5c` |  |
| gibbs energy expression term; _printed: ΔG0 constant term_ | -135000 J/mol |  | UNKNOWN | experimental | [1] Hallstedt 1994; _cites Rigdon 1969_ | Table 7, p. 12, row 13; `ORC-ZPC6I3K6OQ.88232b` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 3.86 J/mol/K |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 3, p. 10, row 12; `ORC-47KE6FMT3F.7c2dd6` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -71650 J/mol |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Boudbne 1992_ | Table 3, p. 10, row 12; `ORC-47KE6FMT3F.8e2af3` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −66110−7.66T\]_ | -7.66 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 70Eln_ | Table 3, p. 9, row 18; `ORC-4P4VV5KMSO.0a903c` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −66110−7.66T\]_ | -66110 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 70Eln_ | Table 3, p. 9, row 18; `ORC-4P4VV5KMSO.ea81b1` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | -0.71 J/mol/K |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 3, p. 10, row 11; `ORC-5CACEBACD2.5a3fec` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -74100 J/mol |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Schmid 1983_ [doi](https://doi.org/10.1007/bf02654367) | Table 3, p. 10, row 11; `ORC-5CACEBACD2.d6877d` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −66940−2.31T\]_ | -66940 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Thompson 1971_ [doi](https://doi.org/10.1179/cmq.1971.10.4.315) | Table 3, p. 9, row 25; `ORC-63FQEFHHHF.1ad93b` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −66940−2.31T\]_ | -2.31 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Thompson 1971_ [doi](https://doi.org/10.1179/cmq.1971.10.4.315) | Table 3, p. 9, row 25; `ORC-63FQEFHHHF.26751d` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | -5.83 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Kayahara 1981_ | Table 3, p. 10, row 5; `ORC-AIJO4YVO4Z.a0c78e` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -67040 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Kayahara 1981_ | Table 3, p. 10, row 5; `ORC-AIJO4YVO4Z.b80df9` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −104580+17.95T\]_ | -104580 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Biswas 1973_ [doi](https://doi.org/10.1179/cmq.1973.12.3.257) | Table 3, p. 9, row 27; `ORC-AVJ3UGWAFW.7dcdc5` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −104580+17.95T\]_ | 17.95 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Biswas 1973_ [doi](https://doi.org/10.1179/cmq.1973.12.3.257) | Table 3, p. 9, row 27; `ORC-AVJ3UGWAFW.a97f16` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −84262+6.76T\]_ | 6.76 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Tsukahara 1970_ [doi](https://doi.org/10.2320/jinstmet1952.34.7_679) | Table 3, p. 9, row 21; `ORC-DYIZSZHQRG.3a6308` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −84262+6.76T\]_ | -84262 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Tsukahara 1970_ [doi](https://doi.org/10.2320/jinstmet1952.34.7_679) | Table 3, p. 9, row 21; `ORC-DYIZSZHQRG.c2777a` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −70270−2.08T\]_ | -70270 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Tankins 1967_ | Table 3, p. 9, row 14; `ORC-DYPM54U76U` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −73800−1.71T\]_ | -73800 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites E Hyt6nen and E Taskinen 1979_ | Table 3, p. 9, row 38; `ORC-H5RBSS44LZ.6b1040` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −73800−1.71T\]_ | -1.71 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites E Hyt6nen and E Taskinen 1979_ | Table 3, p. 9, row 38; `ORC-H5RBSS44LZ.833359` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −41550−19.87T\]_ | -41550 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Belton 1965_ | Table 3, p. 9, row 4; `ORC-HM2XQJ3YL6.a7ccae` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −41550−19.87T\]_ | -19.87 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Belton 1965_ | Table 3, p. 9, row 4; `ORC-HM2XQJ3YL6.d2843f` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −78220+2.65T\]_ | -78220 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Tankins 1972_ | Table 3, p. 9, row 26; `ORC-JMDTWGPEDF.32a9d1` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −78220+2.65T\]_ | 2.65 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Tankins 1972_ | Table 3, p. 9, row 26; `ORC-JMDTWGPEDF.6a5fac` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −129270+38.83T\]_ | 38.83 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Girardi 1950_ | Table 3, p. 9, row 2; `ORC-K4BCCF3XMB.166ed2` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −129270+38.83T\]_ | -129270 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Girardi 1950_ | Table 3, p. 9, row 2; `ORC-K4BCCF3XMB.724675` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −75560−0.06T\]_ | -75560 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Reimann 1967_ | Table 3, p. 9, row 12; `ORC-LPJFLPCMV2` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −90370+10.71T\]_ | 10.71 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Oberg 1973_ [doi](https://doi.org/10.1007/bf02649605) | Table 3, p. 9, row 29; `ORC-M2PFDSR2VR.80d1bb` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −90370+10.71T\]_ | -90370 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Oberg 1973_ [doi](https://doi.org/10.1007/bf02649605) | Table 3, p. 9, row 29; `ORC-M2PFDSR2VR.f37d2e` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −77450+0.38T\]_ | 0.38 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Sano 1956_ | Table 3, p. 9, row 3; `ORC-MB4BHBF2DF.31b076` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −77450+0.38T\]_ | -77450 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Sano 1956_ | Table 3, p. 9, row 3; `ORC-MB4BHBF2DF.8918ab` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −78490+1.96T\]_ | -78490 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ | Table 3, p. 9, row 15; `ORC-MDQJLV4FNQ.99c155` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −78490+1.96T\]_ | 1.96 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Gerlach 1968_ | Table 3, p. 9, row 15; `ORC-MDQJLV4FNQ.a4fb2d` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −76560+0.54T\]_ | 0.54 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 3, p. 9, row 34; `ORC-MIFP5G52IK.5a315e` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −76560+0.54T\]_ | -76560 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites S 1977_ | Table 3, p. 9, row 34; `ORC-MIFP5G52IK.ffd20d` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −74540+0.38T\]_ | -74540 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 71Ois_ | Table 3, p. 9, row 24; `ORC-MYDGARVPIM.5b47b5` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −74540+0.38T\]_ | 0.38 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 71Ois_ | Table 3, p. 9, row 24; `ORC-MYDGARVPIM.a16930` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −81280+2.90T\]_ | -81280 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Kulkami 1973_ | Table 3, p. 9, row 28; `ORC-NAIPV2RTR7.1c3743` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −81280+2.90T\]_ | 2.9 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Kulkami 1973_ | Table 3, p. 9, row 28; `ORC-NAIPV2RTR7.cdcdef` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −136290+30.86T\]_ | 30.86 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 33All_ | Table 3, p. 9, row 1; `ORC-NOP5I3OUER.b629bf` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −136290+30.86T\]_ | -136290 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 33All_ | Table 3, p. 9, row 1; `ORC-NOP5I3OUER.ea90bf` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -77010 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Taskinen 1984_ | Table 3, p. 10, row 9; `ORC-NPQX6GT5V2.a4002d` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 1.07 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Taskinen 1984_ | Table 3, p. 10, row 9; `ORC-NPQX6GT5V2.e1be65` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -74510 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 81Tas1_ | Table 3, p. 10, row 7; `ORC-O7CWOR6FB3` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −81770+4.00T\]_ | -81770 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Fmehan 1969_ | Table 3, p. 9, row 17; `ORC-PGWVSVWANB` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -75500 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 81Ots_ | Table 3, p. 10, row 6; `ORC-U4ETF42L42.8f4cea` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | -0.12 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 81Ots_ | Table 3, p. 10, row 6; `ORC-U4ETF42L42.d97959` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −73220−2.18T\]_ | -2.18 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Fischer 1966_ | Table 3, p. 9, row 7; `ORC-UZZZXEPJQG.51f667` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −73220−2.18T\]_ | -73220 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Fischer 1966_ | Table 3, p. 9, row 7; `ORC-UZZZXEPJQG.b741c4` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −75680+0.44T\]_ | -75680 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 67Stu_ | Table 3, p. 9, row 13; `ORC-XEWLRWZS6W.04966c` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −75680+0.44T\]_ | 0.44 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites ref. 67Stu_ | Table 3, p. 9, row 13; `ORC-XEWLRWZS6W.325c33` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | -3.93 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites E Taskinen and H 1979_ | Table 3, p. 10, row 3; `ORC-XYYIB3IJJO.4c461d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -70310 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites E Taskinen and H 1979_ | Table 3, p. 10, row 3; `ORC-XYYIB3IJJO.74a010` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -78420 J/mol |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994 | Table 3, p. 10, row 13; `ORC-YDS4A2SKH7.479fe0` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 22.24 J/mol/K |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994 | Table 3, p. 10, row 13; `ORC-YDS4A2SKH7.c7a008` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T)_ | 6.9 J/mol/K |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Sigworth 1974_ [doi](https://doi.org/10.1179/cmq.1974.13.3.455) | Table 3, p. 10, row 10; `ORC-YGGG54F4YA.07340d` |  |
| gibbs energy expression term; _printed: ΔG0 (constant term)_ | -85350 J/mol |  | liquid Cu; _alloy: O 0_ | model | [1] Hallstedt 1994; _cites Sigworth 1974_ [doi](https://doi.org/10.1179/cmq.1974.13.3.455) | Table 3, p. 10, row 10; `ORC-YGGG54F4YA.51470b` |  |
| gibbs energy expression term; _printed: ΔG0 \[printed: −72850−2.13T\]_ | -72850 J/mol |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Janke 1978_ | Table 3, p. 9, row 36; `ORC-ZOMAXPKTVH.9c5379` |  |
| gibbs energy expression term; _printed: ΔG0 (coefficient of T) \[printed: −72850−2.13T\]_ | -2.13 J/mol/K |  | liquid Cu; _alloy: O 0_ | experimental | [1] Hallstedt 1994; _cites Janke 1978_ | Table 3, p. 9, row 36; `ORC-ZOMAXPKTVH.ef35e8` |  |

## Sources

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

1. B. Hallstedt, D. Risold, L. J. Gauckler, Thermodynamic assessment of the copper-oxygen system, JPE 15, 483-499 (1994). [doi:10.1007/bf02649399](https://doi.org/10.1007/bf02649399)
2. L. Schramm, G. Behr, W. Löser, K. Wetzig, Thermodynamic Reassessment of the Cu-O Phase Diagram, Journal of Phase Equilibria & Diffusion 26, 605-612 (2005). [doi:10.1361/154770305x74421](https://doi.org/10.1361/154770305x74421)

## 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/).