H–Y system

44 accepted literature values from 2 paper(s) (experimental 8, model 8, DFT 14, unspecified 14); 0 calculated phase diagram(s). 1 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: JSON · CSV · interactive explorer · phases (6) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	8
model	8
DFT	14
unspecified	14

Accepted values by property group
Property group	Values
invariant reaction	10
formation	12
crystal structure	22

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull YH-18Fu

Invariant reactions (literature)

Invariant reactions reported in the literature for the H–Y system (10)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
1639.15	GAS(H2)+HCP(Y)→δ-YH2	GAS(H2): H 1; HCP(Y): H 0.389; δ-YH2: H 0.466	experimental	[1] Peng 2020 cites Lundin 1962 doi	Table 6, p. 7, row 2 report
1634.15	GAS(H2)+HCP(Y)→δ-YH2	GAS(H2): H 1; HCP(Y): H 0.387; δ-YH2: H 0.481	model	[1] Peng 2020	Table 6, p. 7, row 1 report
1594.55	α-Y + Gas(H2)->β-YH2	α-Y: H 0.376; Gas(H2): H 1; β-YH2: H 0.483	unspecified	[2] Fu 2018	Table 2, p. 4, row 2 report
1594.15	GAS(H2)+HCP(Y)→δ-YH2	GAS(H2): H 1; HCP(Y): H 0.376; δ-YH2: H 0.483	unspecified	[1] Peng 2020 cites Fu 2018 doi	Table 6, p. 7, row 3 report
722.15	GAS(H2)+δ-YH2→ε-YH3	GAS(H2): H 1; δ-YH2: H 0.676; ε-YH3: H 0.727	experimental	[1] Peng 2020 cites Fu 2018 doi	Table 6, p. 7, row 7 report
663.15	GAS(H2)+δ-YH2→ε-YH3	GAS(H2): H 1; δ-YH2: H 0.674; ε-YH3: H 0.706	experimental	[1] Peng 2020 cites Yannopoulos 1965 doi	Table 6, p. 7, row 6 report
646.15	GAS(H2)+δ-YH2→ε-YH3	GAS(H2): H 1; δ-YH2: H 0.667; ε-YH3: H 0.733	model	[1] Peng 2020	Table 6, p. 7, row 4 report
642.45	β-YH2 + Gas(H2)->γ-YH3	β-YH2: H 0.676; Gas(H2): H 1; γ-YH3: H 0.727	unspecified	[2] Fu 2018	Table 2, p. 4, row 1 report
642.15	GAS(H2)+δ-YH2→ε-YH3	δ-YH2: H 0.666667; ε-YH3: H 0.75	experimental	[1] Peng 2020 cites Fu 2018 doi	Table 6, p. 7, row 8 report
622.15	GAS(H2)+δ-YH2→ε-YH3	GAS(H2): H 1; δ-YH2: H 0.669; ε-YH3: H 0.714	experimental	[1] Peng 2020 cites Yannopoulos 1965 doi	Table 6, p. 7, row 5 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, H–Y system (12)
Phase	Compound	Value	Class	MP DFT (kJ/mol-atom)	OQMD DFT (kJ/mol-atom)	Source	Location
Trigonal		-245.507 kJ/mol (basis unstated)	unspecified			[1] Peng 2020	Table 4, p. 5, row 7 report
YH (fcc)		-36.5367 kJ/mol-atom	DFT			[1] Peng 2020	Table 4, p. 5, row 1 report
YH (hcp)		-36.5158 kJ/mol-atom	DFT			[1] Peng 2020	Table 4, p. 5, row 5 report
YH2 (fcc)	YH2	-70.8858 kJ/mol-atom	unspecified	-78.756 (mp-aaaabkmc)	-67.808 (oqmd-8288)	[1] Peng 2020	Table 4, p. 5, row 2 report
YH2 (hcp)		-43.8682 kJ/mol-atom	DFT			[1] Peng 2020	Table 4, p. 5, row 6 report
YH3 (Trigonal)	YH3	-61.3768 kJ/mol-atom	unspecified	-70.443 (mp-aaacpbpu)	-58.085 (oqmd-23267)	[1] Peng 2020	Table 4, p. 5, row 7 report
YH3 (fcc)		-54.601 kJ/mol-atom	DFT			[1] Peng 2020	Table 4, p. 5, row 3 report
fcc		-218.404 kJ/mol (basis unstated)	DFT			[1] Peng 2020	Table 4, p. 5, row 3 report
fcc		-212.657 kJ/mol (basis unstated)	unspecified			[1] Peng 2020	Table 4, p. 5, row 2 report
fcc		-73.0734 kJ/mol (basis unstated)	DFT			[1] Peng 2020	Table 4, p. 5, row 1 report
hcp		-131.605 kJ/mol (basis unstated)	DFT			[1] Peng 2020	Table 4, p. 5, row 6 report
hcp		-73.0316 kJ/mol (basis unstated)	DFT			[1] Peng 2020	Table 4, p. 5, row 5 report

Other properties

Crystal structure (22)

Crystal structure, H–Y system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Lattice a printed: a	6.36 Å	0	Trigonal alloy: Y 0.25	unspecified	[1] Peng 2020	Table 4, p. 5, row 7 report
Lattice a printed: a	6.33391 Å	0	YH3 (Trigonal) alloy: Y 0.25	unspecified	[1] Peng 2020	Table 4, p. 5, row 7 report
Lattice a printed: a	5.20697 Å	0	fcc alloy: Y 0.333333	unspecified	[1] Peng 2020	Table 4, p. 5, row 2 report
Lattice a printed: a	5.20701 Å	0	fcc alloy: Y 0.333333	unspecified	[1] Peng 2020	Table 4, p. 5, row 2 report
Lattice a printed: a	4.95037 Å	0	fcc alloy: Y 0.5	DFT	[1] Peng 2020	Table 4, p. 5, row 1 report
Lattice a printed: a	5.16199 Å	0	fcc alloy: Y 0.25	DFT	[1] Peng 2020	Table 4, p. 5, row 3 report
Lattice a printed: a	3.64125 Å	0	hcp alloy: Y 0.5	DFT	[1] Peng 2020	Table 4, p. 5, row 5 report
Lattice a printed: a	3.59237 Å	0	hcp alloy: Y 0.333333	DFT	[1] Peng 2020	Table 4, p. 5, row 6 report
Lattice a	5.207 not_printed	298.15	δ-YH2 alloy: Y 0.333333	experimental	[1] Peng 2020 cites Weaver 1980	Table 1, p. 3, row 2 report
Lattice a	5.207 not_printed	298.15	δ-YH2 alloy: Y 0.333333	unspecified	[1] Peng 2020 cites Weaver 1980	Table 1, p. 3, row 4 report
Lattice a	6.36 not_printed	298.15	ε-YH3 alloy: Y 0.25	experimental	[1] Peng 2020 cites Mansmann 1964	Table 1, p. 3, row 3 report
Lattice c printed: c	6.659 Å	0	Trigonal alloy: Y 0.25	unspecified	[1] Peng 2020	Table 4, p. 5, row 7 report
Lattice c printed: c	6.59997 Å	0	YH3 (Trigonal) alloy: Y 0.25	unspecified	[1] Peng 2020	Table 4, p. 5, row 7 report
Lattice c printed: c	5.50043 Å	0	hcp alloy: Y 0.5	DFT	[1] Peng 2020	Table 4, p. 5, row 5 report
Lattice c printed: c	6.39469 Å	0	hcp alloy: Y 0.333333	DFT	[1] Peng 2020	Table 4, p. 5, row 6 report
Lattice c	6.659 not_printed	298.15	ε-YH3 alloy: Y 0.25	experimental	[1] Peng 2020 cites Mansmann 1964	Table 1, p. 3, row 3 report
Molar volume printed: V0	231.711 Å3		Trigonal alloy: Y 0.25	model	[1] Peng 2020	Table 4, p. 4, row 7 report
Molar volume printed: V0	142.101 Å3		fcc alloy: Y 0.333333	model	[1] Peng 2020	Table 4, p. 4, row 2 report
Molar volume printed: V0	121.727 Å3		fcc alloy: Y 0.5	model	[1] Peng 2020	Table 4, p. 4, row 1 report
Molar volume printed: V0	138.605 Å3		fcc alloy: Y 0.25	model	[1] Peng 2020	Table 4, p. 4, row 3 report
Molar volume printed: V0	72.8017 Å3		hcp alloy: Y 0.333333	model	[1] Peng 2020	Table 4, p. 4, row 6 report
Molar volume printed: V0	63.6316 Å3		hcp alloy: Y 0.5	model	[1] Peng 2020	Table 4, p. 4, row 5 report

Sources

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

Jiaqing Peng, Ming Wu, Fu Du, Fengli Yang, Jianyun Shen, Lijun Wang et al., Thermodynamic modelling of Y–H and Y–Zr–H system aided by first-principles and its application in bulk hydride moderator fabrication, Journal of Nuclear Materials 531, 152035 (2020). doi:10.1016/j.jnucmat.2020.152035
Kai Fu, Xiaojing Jiang, Yanru Guo, Shuan Li, Jie Zheng, Wenhuai Tian et al., Experimental investigation and thermodynamic assessment of the yttrium-hydrogen binary system, Progress in Natural Science: Materials International 28, 332-336 (2018). doi:10.1016/j.pnsc.2018.04.001

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}
}