Na–O–U system

179 accepted literature values from 1 paper(s) (experimental 85, model 31, DFT 28, unspecified 35); 0 calculated phase diagram(s). 6 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

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Accepted values by evidence class
Evidence class	Values
experimental	85
model	31
DFT	28
unspecified	35

Accepted values by property group
Property group	Values
invariant reaction	14
formation	35
heat capacity / entropy / enthalpy	34
crystal structure	95
model expression	1

Invariant reactions (literature)

Invariant reactions reported in the literature for the Na–O–U system (14)
T (K)	Reaction / phases	Class	Source	Location
2532.4	Na2UO4 = UO2 + 2Na(g) + O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 7 report
2476.2	Na2U2O7 = Na2UO4 + UO2 + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 9 report
2341.6	Na4UO5 = Na2UO4 + 2Na(g) + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 5 report
1913.4	Na2U2O7 = 2UO2 + 2Na(g) + 3/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 10 report
1827.1	2Na2UO4 = Na2U2O7 + 2Na(g) + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 8 report
1756.3	Na4UO5 = Na2UO4 + 2Na(g) + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 6 report
1701.9	2NaUO3 = Na2UO4 + UO2	model	[1] Smith 2017	Table 12, p. 19, row 1 report
1645.6	3NaUO3 = Na2U2O7 + UO2 + Na(g)	model	[1] Smith 2017	Table 12, p. 19, row 2 report
1620	Na2U2O7 = 2UO2 + 2Na(g) + 3/2O2(g)	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 12, p. 19, row 14 report
1550	3NaUO3 = Na2U2O7 + UO2 + Na(g)	experimental	[1] Smith 2017 cites Smith 2014	Table 12, p. 19, row 11 report
1358.3	2Na3UO4 = Na4UO5 + UO2 + 2Na(g) + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 3 report
1273	Na4UO5 = NaUO3 + 3Na(g) + O2(g)	experimental	[1] Smith 2017 cites Smith 2014	Table 12, p. 19, row 13 report
1173	Na3UO4 = NaUO3 + 2Na(g) + 1/2O2(g)	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 12, p. 19, row 12 report
944.4	2Na3UO4 = Na4UO5 + UO2 + 2Na(g) + 1/2O2(g)	model	[1] Smith 2017	Table 12, p. 19, row 4 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, Na–O–U system (18)
Phase	Value	T (K)	Class	Source	Location
Na4UO5	-245.7 kJ/mol-atom	298.15	model	[1] Smith 2017	Table 8, p. 12, row 8 report
Na4UO5	-245.7 kJ/mol-atom ± 0.22	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 6 report
Na4UO5	-238.83 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 7 report
NaUO3	-298.98 kJ/mol-atom	298.15	model	[1] Smith 2017	Table 8, p. 12, row 15 report
NaUO3	-298.98 kJ/mol-atom ± 2	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 13 report
NaUO3	-298.92 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 14 report
α-Na2U2O7	-291.255 kJ/mol-atom	298.15	model	[1] Smith 2017	Table 8, p. 12, row 11 report
α-Na2U2O7	-291.255 kJ/mol-atom ± 0.363636	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 9 report
α-Na2U2O7	-284.591 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 10 report
α-Na2UO4	-271.6 kJ/mol-atom	298.15	model	[1] Smith 2017	Table 8, p. 12, row 3 report
α-Na2UO4	-271.1 kJ/mol-atom ± 0.5	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 1 report
α-Na2UO4	-265.443 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 2 report
α-Na3UO4	-253 kJ/mol-atom ± 1	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 16 report
α-Na3UO4	-253 kJ/mol-atom	298.15	model	[1] Smith 2017	Table 8, p. 12, row 18 report
α-Na3UO4	-251.838 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 17 report
β-Na2U2O7	-284.618 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 12 report
β-Na2UO4	-269.229 kJ/mol-atom ± 0.514286	298.15	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 4 report
β-Na2UO4	-264.6 kJ/mol-atom	298.15	DFT	[1] Smith 2017	Table 8, p. 12, row 5 report

Other properties

Formation (17)

Formation, Na–O–U system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-223.47 kJ/mol-atom	298.15	Na4UO5 alloy: O 0.5, U 0.1	DFT	[1] Smith 2017	Table 8, p. 12, row 7 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-230.17 kJ/mol-atom	298.15	Na4UO5 alloy: O 0.5, U 0.1	model	[1] Smith 2017	Table 8, p. 12, row 8 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-230.17 kJ/mol-atom ± 0.29	298.15	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 6 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-282.54 kJ/mol-atom	298.15	NaUO3 alloy: O 0.6, U 0.2	DFT	[1] Smith 2017	Table 8, p. 12, row 14 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-282.16 kJ/mol-atom	298.15	NaUO3 alloy: O 0.6, U 0.2	model	[1] Smith 2017	Table 8, p. 12, row 15 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-282.5 kJ/mol-atom ± 2	298.15	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 13 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-273.773 kJ/mol-atom	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	model	[1] Smith 2017	Table 8, p. 12, row 11 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-273.773 kJ/mol-atom ± 0.363636	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 9 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-284.591 kJ/mol-atom	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 10 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-254.857 kJ/mol-atom	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	model	[1] Smith 2017	Table 8, p. 12, row 3 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-254.186 kJ/mol-atom ± 0.5	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 1 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-249.643 kJ/mol-atom	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 2 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-237.488 kJ/mol-atom ± 1	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 16 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-237.488 kJ/mol-atom	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	model	[1] Smith 2017	Table 8, p. 12, row 18 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-236.65 kJ/mol-atom	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	DFT	[1] Smith 2017	Table 8, p. 12, row 17 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-268.1 kJ/mol-atom	298.15	β-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 12 report
Gibbs energy of formation printed: ΔfG°m(298.15 K)	-248.414 kJ/mol-atom	298.15	β-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 5 report

Heat capacity / entropy / enthalpy (34)

Heat capacity / entropy / enthalpy, Na–O–U system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Entropy printed: S°m(298.15 K)	25.24 J/mol-atom/K	298.15	Na4UO5 alloy: O 0.5, U 0.1	DFT	[1] Smith 2017	Table 8, p. 12, row 7 report
Entropy printed: S°m(298.15 K)	24.75 J/mol-atom/K	298.15	Na4UO5 alloy: O 0.5, U 0.1	model	[1] Smith 2017	Table 8, p. 12, row 8 report
Entropy printed: S°m(298.15 K)	24.75 J/mol-atom/K ± 0.62	298.15	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 6 report
Entropy printed: S°m(298.15 K)	26.86 J/mol-atom/K	298.15	NaUO3 alloy: O 0.6, U 0.2	DFT	[1] Smith 2017	Table 8, p. 12, row 14 report
Entropy printed: S°m(298.15 K)	25.4 J/mol-atom/K	298.15	NaUO3 alloy: O 0.6, U 0.2	model	[1] Smith 2017	Table 8, p. 12, row 15 report
Entropy printed: S°m(298.15 K)	26.56 J/mol-atom/K ± 0.08	298.15	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 13 report
Entropy printed: S°m(298.15 K)	25.0818 J/mol-atom/K	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	model	[1] Smith 2017	Table 8, p. 12, row 11 report
Entropy printed: S°m(298.15 K)	25.0818 J/mol-atom/K ± 0.0909091	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 9 report
Entropy printed: S°m(298.15 K)	30.1182 J/mol-atom/K	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 10 report
Entropy printed: S°m(298.15 K)	24.2857 J/mol-atom/K	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	model	[1] Smith 2017	Table 8, p. 12, row 3 report
Entropy printed: S°m(298.15 K)	23.7143 J/mol-atom/K ± 0.0714286	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 1 report
Entropy printed: S°m(298.15 K)	27.3571 J/mol-atom/K	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 2 report
Entropy printed: S°m(298.15 K)	24.775 J/mol-atom/K ± 0.05	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 16 report
Entropy printed: S°m(298.15 K)	24.775 J/mol-atom/K	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	model	[1] Smith 2017	Table 8, p. 12, row 18 report
Entropy printed: S°m(298.15 K)	25.7875 J/mol-atom/K	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	DFT	[1] Smith 2017	Table 8, p. 12, row 17 report
Entropy printed: S°m(298.15 K)	28.2818 J/mol-atom/K	298.15	β-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 12 report
Entropy printed: S°m(298.15 K)	25.9714 J/mol-atom/K	298.15	β-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 5 report
Heat capacity printed: C°p,m(298.15 K)	21.69 J/mol-atom/K	298.15	Na4UO5 alloy: O 0.5, U 0.1	DFT	[1] Smith 2017	Table 8, p. 12, row 7 report
Heat capacity printed: C°p,m(298.15 K)	22.04 J/mol-atom/K	298.15	Na4UO5 alloy: O 0.5, U 0.1	model	[1] Smith 2017	Table 8, p. 12, row 8 report
Heat capacity printed: C°p,m(298.15 K)	22.06 J/mol-atom/K ± 0.67	298.15	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 6 report
Heat capacity printed: C°p,m(298.15 K)	21.96 J/mol-atom/K	298.15	NaUO3 alloy: O 0.6, U 0.2	DFT	[1] Smith 2017	Table 8, p. 12, row 14 report
Heat capacity printed: C°p,m(298.15 K)	21.82 J/mol-atom/K	298.15	NaUO3 alloy: O 0.6, U 0.2	model	[1] Smith 2017	Table 8, p. 12, row 15 report
Heat capacity printed: C°p,m(298.15 K)	21.774 J/mol-atom/K ± 0.08	298.15	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 13 report
Heat capacity printed: C°p,m(298.15 K)	20.7364 J/mol-atom/K	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	model	[1] Smith 2017	Table 8, p. 12, row 11 report
Heat capacity printed: C°p,m(298.15 K)	20.6636 J/mol-atom/K ± 0.0909091	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 9 report
Heat capacity printed: C°p,m(298.15 K)	20.8636 J/mol-atom/K	298.15	α-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 10 report
Heat capacity printed: C°p,m(298.15 K)	21.0143 J/mol-atom/K	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	model	[1] Smith 2017	Table 8, p. 12, row 3 report
Heat capacity printed: C°p,m(298.15 K)	20.9571 J/mol-atom/K ± 0.0714286	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 1 report
Heat capacity printed: C°p,m(298.15 K)	21.4571 J/mol-atom/K	298.15	α-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 2 report
Heat capacity printed: C°p,m(298.15 K)	21.625 J/mol-atom/K ± 0.05	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Guillaumont 2003	Table 8, p. 12, row 16 report
Heat capacity printed: C°p,m(298.15 K)	21.6 J/mol-atom/K	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	model	[1] Smith 2017	Table 8, p. 12, row 18 report
Heat capacity printed: C°p,m(298.15 K)	21.9625 J/mol-atom/K	298.15	α-Na3UO4 alloy: O 0.5, U 0.125	DFT	[1] Smith 2017	Table 8, p. 12, row 17 report
Heat capacity printed: C°p,m(298.15 K)	20.9636 J/mol-atom/K	298.15	β-Na2U2O7 alloy: O 0.636364, U 0.181818	DFT	[1] Smith 2017	Table 8, p. 12, row 12 report
Heat capacity printed: C°p,m(298.15 K)	21.4429 J/mol-atom/K	298.15	β-Na2UO4 alloy: O 0.571429, U 0.142857	DFT	[1] Smith 2017	Table 8, p. 12, row 5 report

Crystal structure (95)

Crystal structure, Na–O–U system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Lattice a	7.695 Å	0	Na4UO5 alloy: O 0.5, U 0.1	unspecified	[1] Smith 2017	Table 10, p. 13, row 14 report
Lattice a	5.8321 Å	0	NaUO3 alloy: O 0.6, U 0.2	unspecified	[1] Smith 2017	Table 10, p. 13, row 2 report
Lattice a	13.1322 Å	0	α-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 16 report
Lattice a	10.0103 Å	0	α-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 9 report
Lattice a	5.937 Å	0	α-Na3UO4 alloy: O 0.5, U 0.125	unspecified	[1] Smith 2017	Table 10, p. 13, row 5 report
Lattice a	13.125 Å	0	β-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 18 report
Lattice a	5.8598 Å	0	β-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 11 report
Lattice a	12.7617 Å ± 1.400e-4	293	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 15 report
Lattice a	7.5172 Å ± 1.000e-4	295	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Roof 2010 doi	Table 10, p. 13, row 13 report
Lattice a	5.7739 Å ± 2.000e-4	295	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Van 2004 doi	Table 10, p. 13, row 1 report
Lattice a	4.77 Å ± 0.02	295	m-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Scholder 1964 doi	Table 10, p. 13, row 3 report
Lattice a	4.764 Å ± 0.003	295	m-Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 12 report
Lattice a	9.7623 Å ± 3.000e-4	295	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 8 report
Lattice a	5.892 Å ± 0.002	295	α-Na3.16(2)U0.84(2)O4 alloy: O 0.5, U 0.105	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 4 report
Lattice a	5.8079 Å ± 3.000e-4	295	β-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 10 report
Lattice a	9.589 Å ± 0.002	295	β-Na3+xU1-xO4	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 6 report
Lattice a	9.56 Å ± 0.04	295	β-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Marcon 1972	Table 10, p. 13, row 7 report
Lattice a	12.933 Å ± 0.001	773	β-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 17 report
Lattice a	3.987 Å ± 0.003	1323	γ-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 19 report
Lattice b	7.695 Å	0	Na4UO5 alloy: O 0.5, U 0.1	unspecified	[1] Smith 2017	Table 10, p. 13, row 14 report
Lattice b	5.9742 Å	0	NaUO3 alloy: O 0.6, U 0.2	unspecified	[1] Smith 2017	Table 10, p. 13, row 2 report
Lattice b	7.8815 Å	0	α-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 16 report
Lattice b	5.7628 Å	0	α-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 9 report
Lattice b	6.845 Å	0	α-Na3UO4 alloy: O 0.5, U 0.125	unspecified	[1] Smith 2017	Table 10, p. 13, row 5 report
Lattice b	7.881 Å	0	β-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 18 report
Lattice b	6.0265 Å	0	β-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 11 report
Lattice b	7.8384 Å ± 1.000e-4	293	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 15 report
Lattice b	7.5172 Å ± 1.000e-4	295	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Roof 2010 doi	Table 10, p. 13, row 13 report
Lattice b	5.9051 Å ± 2.000e-4	295	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Van 2004 doi	Table 10, p. 13, row 1 report
Lattice b	4.77 Å ± 0.02	295	m-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Scholder 1964 doi	Table 10, p. 13, row 3 report
Lattice b	4.764 Å ± 0.003	295	m-Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 12 report
Lattice b	5.7287 Å ± 2.000e-4	295	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 8 report
Lattice b	6.772 Å ± 0.002	295	α-Na3.16(2)U0.84(2)O4 alloy: O 0.5, U 0.105	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 4 report
Lattice b	5.9753 Å ± 3.000e-4	295	β-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 10 report
Lattice b	9.589 Å ± 0.002	295	β-Na3+xU1-xO4	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 6 report
Lattice b	9.56 Å ± 0.04	295	β-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Marcon 1972	Table 10, p. 13, row 7 report
Lattice b	7.887 Å ± 0.001	773	β-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 17 report
Lattice b	3.987 Å ± 0.003	1323	γ-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 19 report
Lattice c	4.6325 Å	0	Na4UO5 alloy: O 0.5, U 0.1	unspecified	[1] Smith 2017	Table 10, p. 13, row 14 report
Lattice c	8.3699 Å	0	NaUO3 alloy: O 0.6, U 0.2	unspecified	[1] Smith 2017	Table 10, p. 13, row 2 report
Lattice c	6.9292 Å	0	α-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 16 report
Lattice c	3.5236 Å	0	α-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 9 report
Lattice c	5.978 Å	0	α-Na3UO4 alloy: O 0.5, U 0.125	unspecified	[1] Smith 2017	Table 10, p. 13, row 5 report
Lattice c	6.9291 Å	0	β-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 18 report
Lattice c	11.8836 Å	0	β-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 11 report
Lattice c	6.8962 Å ± 9.000e-4	293	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 15 report
Lattice c	4.6325 Å ± 2.000e-4	295	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Roof 2010 doi	Table 10, p. 13, row 13 report
Lattice c	8.2784 Å ± 2.000e-4	295	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Van 2004 doi	Table 10, p. 13, row 1 report
Lattice c	4.77 Å ± 0.02	295	m-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Scholder 1964 doi	Table 10, p. 13, row 3 report
Lattice c	4.764 Å ± 0.003	295	m-Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 12 report
Lattice c	3.4956 Å ± 1.000e-4	295	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 8 report
Lattice c	5.916 Å ± 0.002	295	α-Na3.16(2)U0.84(2)O4 alloy: O 0.5, U 0.105	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 4 report
Lattice c	11.7179 Å ± 6.000e-4	295	β-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 10 report
Lattice c	9.589 Å ± 0.002	295	β-Na3+xU1-xO4	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 6 report
Lattice c	9.56 Å ± 0.04	295	β-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Marcon 1972	Table 10, p. 13, row 7 report
Lattice c	6.9086 Å ± 8.000e-4	773	β-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 17 report
Lattice c	18.491 Å ± 0.003	1323	γ-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 19 report
lattice beta	90 °	0	Na4UO5 alloy: O 0.5, U 0.1	unspecified	[1] Smith 2017	Table 10, p. 13, row 14 report
lattice beta	90 °	0	NaUO3 alloy: O 0.6, U 0.2	unspecified	[1] Smith 2017	Table 10, p. 13, row 2 report
lattice beta	110.994 °	0	α-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 16 report
lattice beta	90 °	0	α-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 9 report
lattice beta	110.54 °	0	α-Na3UO4 alloy: O 0.5, U 0.125	unspecified	[1] Smith 2017	Table 10, p. 13, row 5 report
lattice beta	110.967 °	0	β-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 18 report
lattice beta	90 °	0	β-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 11 report
lattice beta	111.285 ° ± 0.009	293	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 15 report
lattice beta	90 °	295	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Roof 2010 doi	Table 10, p. 13, row 13 report
lattice beta	90 °	295	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Van 2004 doi	Table 10, p. 13, row 1 report
lattice beta	90 °	295	m-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Scholder 1964 doi	Table 10, p. 13, row 3 report
lattice beta	90 °	295	m-Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 12 report
lattice beta	90 °	295	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 8 report
lattice beta	110.65 ° ± 0.02	295	α-Na3.16(2)U0.84(2)O4 alloy: O 0.5, U 0.105	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 4 report
lattice beta	90 °	295	β-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 10 report
lattice beta	90 °	295	β-Na3+xU1-xO4	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 6 report
lattice beta	90 °	295	β-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Marcon 1972	Table 10, p. 13, row 7 report
lattice beta	110.816 ° ± 0.01	773	β-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 17 report
lattice beta	90 °	1323	γ-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 19 report
lattice v	0.27542 nm3	0	Na4UO5 alloy: O 0.5, U 0.1	unspecified	[1] Smith 2017	Table 10, p. 13, row 14 report
lattice v	0.29187 nm3	0	NaUO3 alloy: O 0.6, U 0.2	unspecified	[1] Smith 2017	Table 10, p. 13, row 2 report
lattice v	0.66918 nm3	0	α-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 16 report
lattice v	0.203352 nm3	0	α-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 9 report
lattice v	0.2273 nm3	0	α-Na3UO4 alloy: O 0.5, U 0.125	unspecified	[1] Smith 2017	Table 10, p. 13, row 5 report
lattice v	0.66933 nm3	0	β-Na2U2O7 alloy: O 0.636364, U 0.181818	unspecified	[1] Smith 2017	Table 10, p. 13, row 18 report
lattice v	0.419514 nm3	0	β-Na2UO4 alloy: O 0.571429, U 0.142857	unspecified	[1] Smith 2017	Table 10, p. 13, row 11 report
lattice v	0.64278 nm3 ± 1.000e-4	293	α-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 15 report
lattice v	0.26178 nm3 ± 1.000e-5	295	Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Roof 2010 doi	Table 10, p. 13, row 13 report
lattice v	0.28226 nm3 ± 1.000e-5	295	NaUO3 alloy: O 0.6, U 0.2	experimental	[1] Smith 2017 cites Van 2004 doi	Table 10, p. 13, row 1 report
lattice v	0.10853 nm3 ± 1.000e-4	295	m-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Scholder 1964 doi	Table 10, p. 13, row 3 report
lattice v	0.10812 nm3 ± 1.000e-5	295	m-Na4UO5 alloy: O 0.5, U 0.1	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 12 report
lattice v	0.195496 nm3 ± 1.100e-5	295	α-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 8 report
lattice v	0.22083 nm3 ± 1.000e-5	295	α-Na3.16(2)U0.84(2)O4 alloy: O 0.5, U 0.105	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 4 report
lattice v	0.40665 nm3 ± 3.400e-5	295	β-Na2UO4 alloy: O 0.571429, U 0.142857	experimental	[1] Smith 2017 cites Cordfunke 1995 doi	Table 10, p. 13, row 10 report
lattice v	0.88191 nm3 ± 1.000e-5	295	β-Na3+xU1-xO4	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 6 report
lattice v	0.8737 nm3 ± 1.000e-4	295	β-Na3UO4 alloy: O 0.5, U 0.125	experimental	[1] Smith 2017 cites Marcon 1972	Table 10, p. 13, row 7 report
lattice v	0.6588 nm3 ± 1.300e-4	773	β-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites IJdo 2015 doi	Table 10, p. 13, row 17 report
lattice v	0.25461 nm3 ± 1.000e-5	1323	γ-Na2U2O7 alloy: O 0.636364, U 0.181818	experimental	[1] Smith 2017 cites Smith 2015 doi	Table 10, p. 13, row 19 report

Model expression (1)

Model expression, Na–O–U system
Property	Value	T (K)	Phases / composition	Class	Source	Location	Quote
Chemical potential printed: ΔG_O2^eq (T/K)	expression: −948630 + 263.28T	900	α-Na3UO4 alloy: O 0.5, U 0.125	model	[1] Smith 2017	Table 13, p. 20, row 7 report

Sources

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

A.L. Smith, C. Guéneau, J.-L. Flèche, S. Chatain, O. Beneš, R.J.M. Konings, Thermodynamic assessment of the Na-O and Na-U-O systems: Margin to the safe operation of SFRs, The Journal of Chemical Thermodynamics 114, 93-115 (2017). doi:10.1016/j.jct.2017.04.003

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}
}