Pu system

43 accepted literature values from 5 paper(s) (experimental 18, model 22, unspecified 3); 0 calculated phase diagram(s). 42 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

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

Accepted values by evidence class
Evidence class	Values
experimental	18
model	22
unspecified	3

Accepted values by property group
Property group	Values
invariant reaction	9
phase transition	6
formation	5
heat capacity / entropy / enthalpy	5
crystal structure	18

Invariant reactions (literature)

Invariant reactions reported in the literature for the Pu system (9)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
593	δ-Pu = γ-Pu		model	[1] Guéneau 2008	Table 3, p. 9, row 43 report
488.15	polymorphic: (γPu) ↔ (βPu)	(γPu):	model	[2] Liu 2014	Table 4, p. 4, row 11 report
488.15	polymorphic: (γPu) ↔ (βPu)	(γPu):	experimental	[2] Liu 2014 cites Massalski 1990	Table 4, p. 4, row 10 report
488	γ-Pu = β-Pu		model	[1] Guéneau 2008	Table 3, p. 9, row 44 report
398.15	polymorphic: (βPu) -> (αPu)	(βPu): Pu 1; (αPu): Pu 1	experimental	[2] Liu 2014 cites Okamoto 2000	Table 5, p. 6, row 24 report
398.15	polymorphic: (βPu) ↔ (αPu)		experimental	[2] Liu 2014 cites Massalski 1990	Table 4, p. 4, row 12 report
398.15	polymorphic: (βPu) ↔ (αPu)	(βPu):	model	[2] Liu 2014	Table 4, p. 4, row 13 report
398.15	polymorphic: (βPu) -> (αPu)	(βPu): Pu 1; (αPu): Pu 1	model	[2] Liu 2014	Table 5, p. 6, row 25 report
398	β-Pu = α-Pu		model	[1] Guéneau 2008	Table 3, p. 9, row 45 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, Pu system (5)
Phase	Value	T (K)	Class	Source	Location
α-Pu	0 kJ/mol-atom	298.15	model	[3] Beneš 2014	Table 1, p. 2, row 13 report
β-Pu	3.8809 kJ/mol-atom	298.15	model	[3] Beneš 2014	Table 1, p. 2, row 16 report
γ-Pu	4.4525 kJ/mol-atom	298.15	model	[3] Beneš 2014	Table 1, p. 2, row 19 report
δ-Pu	5.0503 kJ/mol-atom	298.15	model	[3] Beneš 2014	Table 1, p. 2, row 23 report
ϵ-Pu	7.5591 kJ/mol-atom	298.15	model	[3] Beneš 2014	Table 1, p. 2, row 30 report

Other properties

Phase transition (6)

Phase transition, Pu system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Phase transition	397.15 K	397.15	α-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 6 report
Phase transition	488.15 K	488.15	β-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 7 report
Phase transition	593.15 K	593.15	γ-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 8 report
Phase transition	736.15 K	736.15	δ-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 9 report
Phase transition	756.15 K	756.15	δ′-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 10 report
Phase transition	913.15 K	913.15	ε-Pu alloy: Pu 1	model	[4] Perron 2016 cites Dinsdale 1991 doi	Table 1, p. 3, row 11 report

Heat capacity / entropy / enthalpy (5)

Heat capacity / entropy / enthalpy, Pu system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Entropy printed: S0(298.15)	54.461 J/mol-atom/K	298.15	α-Pu	model	[3] Beneš 2014	Table 1, p. 2, row 13 report
Entropy printed: S0(298.15)	64.266 J/mol-atom/K	298.15	β-Pu	model	[3] Beneš 2014	Table 1, p. 2, row 16 report
Entropy printed: S0(298.15)	65.477 J/mol-atom/K	298.15	γ-Pu	model	[3] Beneš 2014	Table 1, p. 2, row 19 report
Entropy printed: S0(298.15)	66.37 J/mol-atom/K	298.15	δ-Pu	model	[3] Beneš 2014	Table 1, p. 2, row 23 report
Entropy printed: S0(298.15)	69.975 J/mol-atom/K	298.15	ϵ-Pu	model	[3] Beneš 2014	Table 1, p. 2, row 30 report

Crystal structure (18)

Crystal structure, Pu system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Lattice a	11.83 Å		β-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 2 report
Lattice a	6.183 Å ± 0.001	298.15	α-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 1 report
Lattice a	3.1587 Å ± 4.000e-4	298.15	γ-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1955 doi	Table 1, p. 2, row 3 report
Lattice a	0.46347 not_printed	298.15	δ-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Ellinger 1956	Table 1, p. 2, row 4 report
Lattice a	3.339 Å ± 0.003	298.15	δ′-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Ellinger 1956	Table 1, p. 2, row 5 report
Lattice a	0.36375 not_printed	298.15	ε-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Ellinger 1956	Table 1, p. 2, row 6 report
Lattice b	10.449 Å		β-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 2 report
Lattice b	4.822 Å ± 0.001	298.15	α-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 1 report
Lattice b	5.7682 Å ± 4.000e-4	298.15	γ-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1955 doi	Table 1, p. 2, row 3 report
Lattice c	9.227 Å		β-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 2 report
Lattice c	10.963 Å ± 0.001	298.15	α-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 1 report
Lattice c	10.162 Å ± 0.002	298.15	γ-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1955 doi	Table 1, p. 2, row 3 report
Lattice c	4.446 Å ± 0.007	298.15	δ′-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Ellinger 1956	Table 1, p. 2, row 5 report
Molar volume printed: V	13.75 cm^3 mol^-1		B.c.c. alloy: Pu 1	unspecified	[5] Ogawa 1993	Table 1, p. 2, row 8 report
Molar volume printed: V	15.02 cm^3 mol^-1		F.c.c. alloy: Pu 1	unspecified	[5] Ogawa 1993	Table 1, p. 2, row 9 report
Molar volume printed: V	14.53 cm^3 mol^-1		Liquid alloy: Pu 1	unspecified	[5] Ogawa 1993	Table 1, p. 2, row 7 report
lattice beta	138.65 °		β-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 2 report
lattice beta	101.79 °	298.15	α-Pu alloy: Pu 1	experimental	[1] Guéneau 2008 cites Zachariasen 1963 doi	Table 1, p. 2, row 1 report

Sources

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

Christine Guéneau, Christian Chatillon, Bo Sundman, Thermodynamic modelling of the plutonium–oxygen system, Journal of Nuclear Materials 378, 257-272 (2008). doi:10.1016/j.jnucmat.2008.06.013
X.J. Liu, Q. He, D. Wang, Y. Lu, M.H. Chen, J.P. Jia et al., Thermodynamic assessments of the Pu–Zn and La–Pu systems, Journal of Nuclear Materials 453, 169-175 (2014). doi:10.1016/j.jnucmat.2014.07.001
O. Beneš, D. Manara, R.J.M. Konings, Thermodynamic assessment of the Th–U–Pu system, Journal of Nuclear Materials 449, 15-22 (2014). doi:10.1016/j.jnucmat.2014.02.001
A. Perron, P.E.A. Turchi, A. Landa, B. Oudot, B. Ravat, F. Delaunay, Thermodynamic assessments and inter-relationships between systems involving Al, Am, Ga, Pu, and U, Journal of Nuclear Materials 482, 187-200 (2016). doi:10.1016/j.jnucmat.2016.09.012
Toru Ogawa, Alloying behaviour among U, Np, Pu and Am predicted with the Brewer valence bond model, Journal of Alloys and Compounds 194, 1-7 (1993). doi:10.1016/0925-8388(93)90636-2

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 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); 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.

@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_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}
}