O–Y system

40 accepted literature values from 3 paper(s) (experimental 24, model 14, unspecified 2); 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 · CSV · interactive explorer · phases (10) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	24
model	14
unspecified	2

Accepted values by property group
Property group	Values
invariant reaction	10
phase transition	17
formation	1
heat capacity / entropy / enthalpy	7
crystal structure	3
other property	2

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull YO-04Che · CALPHAD hull YO-05Che · CALPHAD hull YO-07Dju · CALPHAD hull YO-96Gro · CALPHAD hull YO-98Swa-LB · CALPHAD hull YO-98Swa-orig

Invariant reactions (literature)

Invariant reactions reported in the literature for the O–Y system (10)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
4921	congruent melting: L* -> gas* (P = 1 bar)	L: O 0.371; gas: O 0.371	model	[1] Djurovic 2007	Table 2, p. 6, row 10 report
2718	congruent melting: L* -> β-Y2O3*	L: O 0.598; β-Y2O3: O 0.598	model	[1] Djurovic 2007	Table 2, p. 6, row 8 report
2712	congruent melting: L* -> β-Y2O3*	L: O 0.6, Y 0.4; β-Y2O3: O 0.6, Y 0.4	experimental	[1] Djurovic 2007 cites Foex 1977	Table 2, p. 6, row 9 report
2600	other: β-Y2O3* -> α-Y2O3 + L	β-Y2O3: O 0.588; α-Y2O3: O 0.6, Y 0.4	model	[1] Djurovic 2007	Table 2, p. 6, row 7 report
1943	congruent melting: L* -> β-Y*	L: O 0.226; β-Y: O 0.226	experimental	[1] Djurovic 2007 cites Tucker 1964	Table 2, p. 6, row 6 report
1943	congruent melting: L* -> β-Y*	L: O 0.23; β-Y: O 0.23	model	[1] Djurovic 2007	Table 2, p. 6, row 5 report
1833	eutectic: L* -> β-Y + gα-Y2O3	L: O 0.373; gα-Y2O3: O 0.6, Y 0.4	model	[1] Djurovic 2007	Table 2, p. 6, row 3 report
1833	eutectic: L* -> β-Y + gα-Y2O3	L: O 0.373; gα-Y2O3: O 0.6, Y 0.4	experimental	[1] Djurovic 2007 cites Tucker 1964	Table 2, p. 6, row 4 report
1453	eutectoid: β-Y* -> α-Y + gα-Y2O3	β-Y: O 0.18; gα-Y2O3: O 0.6, Y 0.4	model	[1] Djurovic 2007	Table 2, p. 6, row 1 report
1453	eutectoid: β-Y* -> α-Y + gα-Y2O3	β-Y: O 0.18; gα-Y2O3: O 0.6, Y 0.4	experimental	[1] Djurovic 2007 cites Tucker 1964	Table 2, p. 6, row 2 report

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.

Enthalpies of formation, O–Y system (1)
Phase	Compound	Value	T (K)	Class	MP DFT (kJ/mol-atom)	OQMD DFT (kJ/mol-atom)	Source	Location	Quote
C-Y2O3	Y2O3	-386.56 kJ/mol-atom	298.15	model	-383.134 (mp-aaaaadya)	-367.434 (oqmd-3427)	[2] ZINKEVICH 2007	Table 6.1, p. 24, row 7 report

Other properties

Phase transition (17)

Phase transition, O–Y system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Phase transition	298.15 K	298.15	polymorphic: B ⇒ A alloy: O 0.6, Y 0.4	unspecified	[2] ZINKEVICH 2007 cites Ma 2002	Table 2.3, p. 10, row 8 report
Phase transition	298.15 K	298.15	polymorphic: B ⇒ A alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Husson 1999	Table 2.3, p. 10, row 7 report
Phase transition	298.15 K	298.15	polymorphic: C ⇒ B alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Husson 1999	Table 2.3, p. 10, row 5 report
Phase transition	298.15 K	298.15	polymorphic: C ⇒ B alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Atou 1990	Table 2.3, p. 10, row 4 report
Phase transition	298.15 K	298.15	polymorphic: C ⇒ B alloy: O 0.6, Y 0.4	unspecified	[2] ZINKEVICH 2007 cites Ma 2002	Table 2.3, p. 10, row 6 report
Phase transition	1273 K	1273	polymorphic: C ⇒ B alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Hoekstra 1966	Table 2.3, p. 10, row 3 report
Phase transition	2512 K	2512	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Swamy 1999	Table 2.1, p. 6, row 9 report
Phase transition	2565 K	2565	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Adylov 1987	Table 2.1, p. 6, row 6 report
Phase transition	2573 K	2573	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Coutures 1976	Table 2.1, p. 6, row 2 report
Phase transition	2573 K	2573	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Glushkova 1988	Table 2.1, p. 6, row 7 report
Phase transition	2581 K	2581	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Navrotsky 2005	Table 2.1, p. 6, row 10 report
Phase transition	2583 K	2583	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Foex 1966	Table 2.1, p. 6, row 1 report
Phase transition	2600 K	2600	polymorphic: C <=> H alloy: O 0.6, Y 0.4	model	[2] ZINKEVICH 2007	Table 2.2, p. 8, row 20 report
Phase transition	2600 K	2600	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Shpilrain 1976	Table 2.1, p. 6, row 5 report
Phase transition	2623 K	2623	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Andrievskaya 1997	Table 2.1, p. 6, row 8 report
Phase transition	2623 K	2623	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Tresvyatkii 1971	Table 2.1, p. 6, row 3 report
Phase transition	2663 K	2663	polymorphic: C ⟺ H alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Shevtchenko 1985	Table 2.1, p. 6, row 4 report

Heat capacity / entropy / enthalpy (7)

Heat capacity / entropy / enthalpy, O–Y system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Entropy printed: ΔS	4.08 J mol^-1 K^-1		UNKNOWN alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Hoekstra 1966	Table 5.1, p. 18, row 2 report
Entropy printed: ΔS	4.08 J mol−1 K−1		Y2O3 alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Hoekstra 1966	Table 5.1, p. 18, row 2 report
Entropy printed: °S	98.96 unknown	298.15	C-Y2O3 alloy: O 0.6, Y 0.4	model	[2] ZINKEVICH 2007	Table 6.1, p. 24, row 7 report
Entropy printed: ΔS	18.5 J mol^-1 K^-1	2581	UNKNOWN alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Navrotsky 2005	Table 5.1, p. 18, row 4 report
Entropy printed: ΔS	18.5 J mol−1 K−1	2581	Y2O3 alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Navrotsky 2005	Table 5.1, p. 18, row 4 report
Entropy printed: ΔS	9.654 J mol^-1 K^-1	2600	UNKNOWN alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Shpilrain 1976	Table 5.1, p. 18, row 3 report
Entropy printed: ΔS	9.654 J mol−1 K−1	2600	Y2O3 alloy: O 0.6, Y 0.4	experimental	[2] ZINKEVICH 2007 cites Shpilrain 1976	Table 5.1, p. 18, row 3 report

Crystal structure (3)

Crystal structure, O–Y system
Property	Value	T (K)	Phases / composition	Class	Source	Location
lattice molar volume	40.385 cm3 mol-1	298.15	Y2O3 (A-type) alloy: O 0.6, Y 0.4	model	[2] ZINKEVICH 2007	Table 3.1, p. 12, row 2 report
lattice molar volume	41.132 cm3 mol-1	298.15	Y2O3 (B-type) alloy: O 0.6, Y 0.4	model	[2] ZINKEVICH 2007	Table 3.1, p. 12, row 2 report
lattice molar volume	44.804 cm3 mol-1	298.15	Y2O3 (C-type) alloy: O 0.6, Y 0.4	model	[2] ZINKEVICH 2007	Table 3.1, p. 12, row 2 report

Other property (2)

Other property, O–Y system
Property	Value	T (K)	Phases / composition	Class	Source	Location	Quote
Other printed: transition enthalpy	19 kJ mol 21	2600	a-Y2O3	model	[3] Swamy 1998	p. 3 report	This corresponds to a transition enthalpy of 19 kJ mol 21 at → b2600 K, the transition temperature taken here for a ← Y 2 O 3 .
Other printed: enthalpy	68 kJ mol 21	2712		model	[3] Swamy 1998	p. 3 report	For a melting temperature of 2712 K taken here for yttria, the Wu and Pelton entropy would translate to an enthalpy value of about 68 kJ mol 21 .

Sources

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

Dejan Djurovic, Matvei Zinkevich, Fritz Aldinger, Thermodynamic modeling of the yttrium–oxygen system, Calphad 31, 560-566 (2007). doi:10.1016/j.calphad.2007.01.010
M ZINKEVICH, Thermodynamics of rare earth sesquioxides, Progress in Materials Science 52, 597-647 (2007). doi:10.1016/j.pmatsci.2006.09.002
Varghese Swamy, Hans J. Seifert, Fritz Aldinger, Thermodynamic properties of Y2O3 phases and the yttrium–oxygen phase diagram, Journal of Alloys and Compounds 269, 201-207 (1998). doi:10.1016/s0925-8388(98)00245-x

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). doi: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). doi: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). doi: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.

@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}
}