O–Pb system

207 accepted literature values from 1 paper(s) (experimental 147, model 37, unspecified 23); 0 calculated phase diagram(s). 12 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: JSON · CSV · interactive explorer · phases (13) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	147
model	37
unspecified	23

Accepted values by property group
Property group	Values
invariant reaction	44
phase transition	32
formation	31
heat capacity / entropy / enthalpy	33
activity / EMF / Gibbs energy	2
model expression	65

Convex hulls: Materials Project DFT hull · OQMD DFT hull

Invariant reactions (literature)

Invariant reactions reported in the literature for the O–Pb system (44)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
1807	L = L1 + L2	L1: Pb 0.704; L2: Pb 0.704	model	[1] Risold 1998	Table 8, p. 8, row 17 report
1583	L = L1 + L2	L1: Pb 0.72; L2: Pb 0.72	experimental	[1] Risold 1998 cites Isecke 1977	Table 8, p. 8, row 16 report
1170	L2 = L1 + PbO-M	L1: Pb 0.9985	experimental	[1] Risold 1998 cites Szware 1972	Table 8, p. 8, row 8 report
1159	L2 = L1 + PbO-M	L1: Pb 0.99104	experimental	[1] Risold 1998 cites ref. 64Alc	Table 8, p. 8, row 7 report
1159	L2 + PbO-M + Pb3O4-T	L2: Pb 0.5	model	[1] Risold 1998	Table 8, p. 8, row 19 report
1159	L2 = L1 + PbO-M	L1: Pb 0.9905	experimental	[1] Risold 1998 cites ref. 55Ric	Table 8, p. 8, row 6 report
1157	L2 = L1 + PbO-M	L2: Pb 0.501; L1: Pb 0.991	model	[1] Risold 1998	Table 8, p. 8, row 15 report
1148	L2 + PbO-M + Pb3O4-T		experimental	[1] Risold 1998 cites White 1964 doi	Table 8, p. 8, row 18 report
1146	L2 = L1 + PbO-M	L2: Pb 0.501; L1: Pb 0.99485	experimental	[1] Risold 1998 cites Kuxmann 1974	Table 8, p. 8, row 9 report
1145	L2 = L1 + PbO-M	L1: Pb 0.9916	experimental	[1] Risold 1998 cites Taskinen 1979	Table 8, p. 8, row 12 report
1145	L2 = L1 + PbO-M	L1: Pb 0.9915	experimental	[1] Risold 1998 cites Wriedt 1994	Table 8, p. 8, row 14 report
1143	L2 = L1 + PbO-M	L2: Pb 0.501; L1: Pb 0.9911	experimental	[1] Risold 1998 cites Isecke 1977	Table 8, p. 8, row 11 report
1143	L2 = L1 + PbO-M	L1: Pb 0.9911	experimental	[1] Risold 1998 cites Charl 1976	Table 8, p. 8, row 10 report
1142	L2 = L1 + PbO-M		experimental	[1] Risold 1998 cites Ya 1981	Table 8, p. 8, row 13 report
835	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998 cites M 1976	Table 9, p. 12, row 20 report
820	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998 cites ref. 1897Lec	Table 9, p. 12, row 17 report
810	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998 cites Reinders 1914 doi	Table 9, p. 12, row 18 report
810	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998 cites Otto 1966 doi	Table 9, p. 12, row 19 report
808	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998	Table 9, p. 12, row 22 report
807	Pb3O4-T = PbO-M + O2		model	[1] Risold 1998	Table 9, p. 12, row 23 report
803	Pb3O4-T = PbO-M + O2		experimental	[1] Risold 1998 cites Ya 1981	Table 9, p. 12, row 21 report
662	Pb12O17 = Pb3O4-T + Pb12O19		model	[1] Risold 1998	Table 8, p. 8, row 21 report
653	Pb12O17 = Pb3O4-T + Pb12O19		experimental	[1] Risold 1998 cites White 1964 doi	Table 8, p. 8, row 20 report
647	Pb12O17 = Pb3O4-T + O2		experimental	[1] Risold 1998 cites Buffer 1956	Table 9, p. 12, row 13 report
638	Pb12O17 = Pb3O4-T + O2		experimental	[1] Risold 1998 cites M 1976	Table 9, p. 12, row 15 report
623	Pb12O19 = Pb12O17 + O2		experimental	[1] Risold 1998 cites BystrSm 1946	Table 9, p. 12, row 9 report
619	Pb12O17 = Pb3O4-T + O2		experimental	[1] Risold 1998 cites Otto 1966 doi	Table 9, p. 12, row 14 report
619	Pb12O19 = Pb12O17 + O2		experimental	[1] Risold 1998 cites Otto 1966 doi	Table 9, p. 12, row 11 report
610	Pb12O17 = Pb3O4-T + O2		model	[1] Risold 1998	Table 9, p. 12, row 16 report
600.6	L1 = Pb + PbO-L	L1: Pb 0.999999	model	[1] Risold 1998	Table 8, p. 8, row 5 report
600	L1 = Pb + PbO-L	L1: Pb 0.99994	experimental	[1] Risold 1998 cites Kuxmann 1974	Table 8, p. 8, row 2 report
600	L1 = Pb + PbO-L	L1: Pb 1	experimental	[1] Risold 1998 cites Reinert 1976	Table 8, p. 8, row 3 report
600	L1 = Pb + PbO-L	L1: Pb 0.999999	experimental	[1] Risold 1998 cites Wriedt 1994	Table 8, p. 8, row 4 report
600	L1 = Pb + PbO-L	L1: Pb 0.999999	experimental	[1] Risold 1998 cites ref. 55Ric	Table 8, p. 8, row 1 report
597	Pb12O19 = Pb12O17 + O2		experimental	[1] Risold 1998 cites Buffer 1956	Table 9, p. 12, row 10 report
567	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites Krustinsons 1937 doi	Table 9, p. 12, row 4 report
563	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites Hempel 1912 doi	Table 9, p. 12, row 2 report
553	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites Carnelley 1888	Table 9, p. 12, row 1 report
553	Pb12O19 = Pb12O17 + O2		model	[1] Risold 1998	Table 9, p. 12, row 12 report
553	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites Buffer 1956	Table 9, p. 12, row 5 report
553	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites ref. 29Mol	Table 9, p. 12, row 3 report
545	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites M 1976	Table 9, p. 12, row 7 report
535	PbO2-I = Pb12O19 + O2		experimental	[1] Risold 1998 cites Otto 1966 doi	Table 9, p. 12, row 6 report
502	PbO2-I = Pb12O19 + O2		model	[1] Risold 1998	Table 9, p. 12, row 8 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–Pb system (13)
Phase	Compound	Value	T (K)	Class	MP DFT (kJ/mol-atom)	OQMD DFT (kJ/mol-atom)	Source	Location
Pb12O17		-104.58 kJ/mol-atom	298.15	model			[1] Risold 1998	Table 1, p. 1, row 17 report
Pb12O19		-100.368 kJ/mol-atom	298.15	model			[1] Risold 1998	Table 1, p. 1, row 18 report
Pb3O4-T	Pb3O4	-104.839 kJ/mol-atom	298.15	model	-139.612 (mp-aaaabhmn)	-123.983 (oqmd-669607)	[1] Risold 1998	Table 1, p. 1, row 14 report
Pb3O4-T	Pb3O4	-102.669 kJ/mol-atom	298.15	experimental	-139.612 (mp-aaaabhmn)	-123.983 (oqmd-669607)	[1] Risold 1998 cites Espada 1970 doi	Table 1, p. 1, row 12 report
Pb3O4-T	Pb3O4	-102.669 kJ/mol-atom	298.15	unspecified	-139.612 (mp-aaaabhmn)	-123.983 (oqmd-669607)	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 13 report
PbO-L	PbO	-109.704 kJ/mol-atom	298.15	unspecified	-141.744 (mp-aaabmglh)	-128.56 (oqmd-2074732)	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 1 report
PbO-L	PbO	-109.528 kJ/mol-atom	298.15	model	-141.744 (mp-aaabmglh)	-128.56 (oqmd-2074732)	[1] Risold 1998	Table 1, p. 1, row 2 report
PbO-M	PbO	-109.031 kJ/mol-atom	298.15	experimental	-141.744 (mp-aaabmglh)	-128.56 (oqmd-2074732)	[1] Risold 1998 cites Espada 1970 doi	Table 1, p. 1, row 6 report
PbO-M	PbO	-109.031 kJ/mol-atom	298.15	unspecified	-141.744 (mp-aaabmglh)	-128.56 (oqmd-2074732)	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 7 report
PbO-M	PbO	-108.721 kJ/mol-atom	298.15	model	-141.744 (mp-aaabmglh)	-128.56 (oqmd-2074732)	[1] Risold 1998	Table 1, p. 1, row 8 report
PbO2-I.	PbO2	-93.9067 kJ/mol-atom	298.15	model	-125.396 (mp-aaaaberd)	-107.539 (oqmd-4264)	[1] Risold 1998	Table 1, p. 1, row 22 report
PbO2-I.	PbO2	-91.504 kJ/mol-atom	298.15	experimental	-125.396 (mp-aaaaberd)	-107.539 (oqmd-4264)	[1] Risold 1998 cites Espada 1970 doi	Table 1, p. 1, row 20 report
PbO2-I.	PbO2	-91.49 kJ/mol-atom	298.15	unspecified	-125.396 (mp-aaaaberd)	-107.539 (oqmd-4264)	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 21 report

Other properties

Phase transition (32)

Phase transition, O–Pb system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Phase transition	423 K	423	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Le 1940	Table 2, p. 3, row 6 report
Phase transition	760.5 K	760.5	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites ref. 46Kam	Table 2, p. 3, row 9 report
Phase transition	761 K	761	polymorphic: PbO-L <-> PbO-M	unspecified	[1] Risold 1998 cites ref. 46Pam	Table 2, p. 3, row 10 report
Phase transition	762 K	762	polymorphic: PbO-L <-> PbO-M	model	[1] Risold 1998	Table 2, p. 3, row 16 report
Phase transition	762 K	762	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Cohen 1934 doi	Table 2, p. 3, row 4 report
Phase transition	762 K	762	polymorphic: PbO-L <-> PbO-M	model	[1] Risold 1998 cites Chase 1985	Table 2, p. 3, row 14 report
Phase transition	763 K	763	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Coussaert 1968	Table 2, p. 3, row 12 report
Phase transition	763 K	763	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Peterson 1941	Table 2, p. 3, row 8 report
Phase transition	803 K	803	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites ref. 36Ren1	Table 2, p. 3, row 5 report
Phase transition	813 K	813	polymorphic: PbO-L <-> PbO-M	model	[1] Risold 1998 cites Wriedt 1994	Table 2, p. 3, row 15 report
Phase transition	813.5 K	813.5	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Rooymans 1968 doi	Table 2, p. 3, row 13 report
Phase transition	816 K	816	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites White 1961	Table 2, p. 3, row 11 report
Phase transition	823 K	823	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Le 1940	Table 2, p. 3, row 7 report
Phase transition	853 K	853	polymorphic: PbO-L <-> PbO-M	unspecified	[1] Risold 1998 cites ref. 1897Lec	Table 2, p. 3, row 1 report
Phase transition	860 K	860	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites EM 1921	Table 2, p. 3, row 3 report
Phase transition	893 K	893	polymorphic: PbO-L <-> PbO-M	experimental	[1] Risold 1998 cites Ruer 1906 doi	Table 2, p. 3, row 2 report
Phase transition	1103 K	1103	congruent transformation: [1897Lec]	unspecified	[1] Risold 1998 cites ref. 1897Lec	Table 5, p. 5, row 1 report
Phase transition	1143 K	1143	congruent transformation: [22Bel]	experimental	[1] Risold 1998 cites Belladen 1922	Table 5, p. 5, row 7 report
Phase transition	1143 K	1143	congruent transformation: [81Kha]	unspecified	[1] Risold 1998 cites Ya 1981	Table 5, p. 5, row 15 report
Phase transition	1149 K	1149	congruent transformation: [09Hil]	unspecified	[1] Risold 1998 cites ref. 09Hil	Table 5, p. 5, row 4 report
Phase transition	1151 K	1151	congruent transformation: [21Jae]	experimental	[1] Risold 1998 cites EM 1921	Table 5, p. 5, row 6 report
Phase transition	1152 K	1152	congruent transformation: [08Sch]	unspecified	[1] Risold 1998 cites ref. 08Sch	Table 5, p. 5, row 2 report
Phase transition	1157 K	1157	congruent transformation: [34Coh]	experimental	[1] Risold 1998 cites Cohen 1934 doi	Table 5, p. 5, row 8 report
Phase transition	1158 K	1158	congruent transformation: [64Kna]	experimental	[1] Risold 1998 cites Knacke 1964	Table 5, p. 5, row 14 report
Phase transition	1159 K	1159	congruent transformation: This work	model	[1] Risold 1998	Table 5, p. 5, row 16 report
Phase transition	1159 K	1159	congruent transformation: [34Gel]	experimental	[1] Risold 1998 cites R 1934	Table 5, p. 5, row 9 report
Phase transition	1159 K	1159	congruent transformation: [36Kra]	unspecified	[1] Risold 1998 cites ref. 36Kra	Table 5, p. 5, row 10 report
Phase transition	1159 K	1159	congruent transformation: [39Leb]	experimental	[1] Risold 1998 cites Le 1940	Table 5, p. 5, row 11 report
Phase transition	1159 K	1159	congruent transformation: [63Sch]	model	[1] Risold 1998 cites Schneider 1964	Table 5, p. 5, row 13 report
Phase transition	1161 K	1161	congruent transformation: [09Coo]	unspecified	[1] Risold 1998 cites ref. 09Coo	Table 5, p. 5, row 3 report
Phase transition	1161 K	1161	congruent transformation: [12Kro]	experimental	[1] Risold 1998 cites Kroll 1912 doi	Table 5, p. 5, row 5 report
Phase transition	1170 K	1170	congruent transformation: [61Rod]	experimental	[1] Risold 1998 cites Rodigina 1961	Table 5, p. 5, row 12 report

Formation (18)

Formation, O–Pb system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Entropy of formation printed: ΔS (transformation)	2.39 J/mol (basis unstated)/K	298.15	PbO alloy: Pb 0.5	model	[1] Risold 1998	Table 3, p. 3, row 3 report
Entropy of formation printed: ΔS (transformation)	1.35 J/mol (basis unstated)/K	762	PbO alloy: Pb 0.5	model	[1] Risold 1998	Table 3, p. 3, row 4 report
Entropy of formation printed: ΔS (transformation)	0.79 J/mol (basis unstated)/K	816	PbO alloy: Pb 0.5	experimental	[1] Risold 1998 cites White 1961	Table 3, p. 3, row 5 report
Gibbs energy of formation printed: ΔfG298	-86.5045 kJ/mol-atom	298.15	Pb12O17 alloy: Pb 0.413793	model	[1] Risold 1998	Table 1, p. 1, row 17 report
Gibbs energy of formation printed: ΔfG298	-82.3885 kJ/mol-atom	298.15	Pb12O19 alloy: Pb 0.387097	model	[1] Risold 1998	Table 1, p. 1, row 25 report
Gibbs energy of formation printed: ΔfG298	-81.74 kJ/mol-atom	298.15	Pb12O19 alloy: Pb 0.387097	experimental	[1] Risold 1998 cites E Chattier 1963	Table 1, p. 1, row 19 report
Gibbs energy of formation printed: ΔfG298	-88.17 kJ/mol-atom	298.15	Pb3O4-T alloy: Pb 0.428571	experimental	[1] Risold 1998 cites E Chattier 1963	Table 1, p. 1, row 16 report
Gibbs energy of formation printed: ΔfG298	-85.3297 kJ/mol-atom	298.15	Pb3O4-T alloy: Pb 0.428571	experimental	[1] Risold 1998 cites Andrews 1934 doi	Table 1, p. 1, row 15 report
Gibbs energy of formation printed: ΔfG298	-87.8996 kJ/mol-atom	298.15	Pb3O4-T alloy: Pb 0.428571	model	[1] Risold 1998	Table 1, p. 1, row 14 report
Gibbs energy of formation printed: ΔfG298	-85.9437 kJ/mol-atom	298.15	Pb3O4-T alloy: Pb 0.428571	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 13 report
Gibbs energy of formation printed: ΔfG298	-94.4685 kJ/mol-atom	298.15	PbO-L alloy: Pb 0.5	model	[1] Risold 1998	Table 1, p. 1, row 2 report
Gibbs energy of formation printed: ΔfG298	-94.5205 kJ/mol-atom	298.15	PbO-L alloy: Pb 0.5	experimental	[1] Risold 1998 cites D 1923	Table 1, p. 1, row 3 report
Gibbs energy of formation printed: ΔfG298	-94.6415 kJ/mol-atom	298.15	PbO-L alloy: Pb 0.5	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 1 report
Gibbs energy of formation printed: ΔfG298	-94.018 kJ/mol-atom	298.15	PbO-M alloy: Pb 0.5	model	[1] Risold 1998	Table 1, p. 1, row 8 report
Gibbs energy of formation printed: ΔfG298	-94.3235 kJ/mol-atom	298.15	PbO-M alloy: Pb 0.5	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 7 report
Gibbs energy of formation printed: ΔfG298	-74.2247 kJ/mol-atom	298.15	PbO2-I. alloy: Pb 0.333333	model	[1] Risold 1998	Table 1, p. 1, row 22 report
Gibbs energy of formation printed: ΔfG298	-72.983 kJ/mol-atom	298.15	PbO2-I. alloy: Pb 0.333333	unspecified	[1] Risold 1998 cites ref. 29Mil	Table 1, p. 1, row 23 report
Gibbs energy of formation printed: ΔfG298	-71.799 kJ/mol-atom	298.15	PbO2-I. alloy: Pb 0.333333	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 21 report

Heat capacity / entropy / enthalpy (33)

Heat capacity / entropy / enthalpy, O–Pb system
Property	Value	T (K)	Phases / composition	Class	Source	Location	Quote
Entropy printed: ΔS	21.2 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charette 1968 doi	Table 6, p. 5, row 6 report
Entropy printed: ΔS	23.6 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Mat1	Table 6, p. 5, row 5 report
Entropy printed: ΔS	21.9 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Rodigina 1961	Table 6, p. 5, row 3 report
Entropy printed: ΔS	24.9 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1975	Table 6, p. 5, row 13 report
Entropy printed: ΔS	24.7 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1973 doi	Table 6, p. 5, row 10 report
Entropy printed: ΔS	26.4 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Iwase 1975 doi	Table 6, p. 5, row 12 report
Entropy printed: ΔS	22.2 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Taskinen 1979	Table 6, p. 5, row 15 report
Entropy printed: ΔS	24.5 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charl 1976	Table 6, p. 5, row 14 report
Entropy printed: ΔS	25.1 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 55Ric	Table 6, p. 5, row 2 report
Entropy printed: ΔS	21.3 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Szware 1972	Table 6, p. 5, row 9 report
Entropy printed: ΔS	24.3 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 75Cal	Table 6, p. 5, row 11 report
Entropy printed: ΔS	24 J/mol·K		PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites ICT 1971	Table 6, p. 5, row 7 report
Entropy printed: ΔS	22.9 J/mol·K		PbO-M alloy: Pb 0.5	model	[1] Risold 1998	Table 6, p. 5, row 16 report
Entropy printed: S	76.4 J/mol 9K	298.15		experimental	[1] Risold 1998 cites ref. 29Mil	p. 12 report	The data of [29Mil] led to the value of 76.4 J/mol 9K for the entropy at 298 K, whereas [68Dui] obtained the value 71.8 J/mol. K.
Entropy printed: S	71.8 J/mol. K	298.15		experimental	[1] Risold 1998 cites Duisman 1968 doi	p. 12 report	The data of [29Mil] led to the value of 76.4 J/mol 9K for the entropy at 298 K, whereas [68Dui] obtained the value 71.8 J/mol. K.
Entropy printed: S298	27.2759 J/mol-atom/K	298.15	Pb12O17 alloy: Pb 0.413793	model	[1] Risold 1998	Table 1, p. 1, row 17 report
Entropy printed: S298	27.6129 J/mol-atom/K	298.15	Pb12O19 alloy: Pb 0.387097	model	[1] Risold 1998	Table 1, p. 1, row 18 report
Entropy printed: S298	29.5714 J/mol-atom/K	298.15	Pb3O4-T alloy: Pb 0.428571	model	[1] Risold 1998	Table 1, p. 1, row 14 report
Entropy printed: S298	30.2857 J/mol-atom/K	298.15	Pb3O4-T alloy: Pb 0.428571	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 13 report
Entropy printed: S298	33.15 J/mol-atom/K	298.15	PbO-L alloy: Pb 0.5	model	[1] Risold 1998	Table 1, p. 1, row 2 report
Entropy printed: S298	32.65 J/mol-atom/K	298.15	PbO-L alloy: Pb 0.5	experimental	[1] Risold 1998 cites King 1958 doi	Table 1, p. 1, row 5 report
Entropy printed: S298	33.15 J/mol-atom/K	298.15	PbO-L alloy: Pb 0.5	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 1 report
Entropy printed: ΔS	2.39 J/mol · K	298.15	PbO-L + PbO-M	model	[1] Risold 1998	Table 3, p. 3, row 3 report
Entropy printed: S298	34.35 J/mol-atom/K	298.15	PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Kostryukov 1960	Table 1, p. 1, row 11 report
Entropy printed: S298	33.7 J/mol-atom/K	298.15	PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites King 1958 doi	Table 1, p. 1, row 10 report
Entropy printed: S298	34.35 J/mol-atom/K	298.15	PbO-M alloy: Pb 0.5	model	[1] Risold 1998	Table 1, p. 1, row 8 report
Entropy printed: S298	34.35 J/mol-atom/K	298.15	PbO-M alloy: Pb 0.5	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 7 report
Entropy printed: S298	23.9333 J/mol-atom/K	298.15	PbO2-I. alloy: Pb 0.333333	model	[1] Risold 1998	Table 1, p. 1, row 22 report
Entropy printed: S298	23.9333 J/mol-atom/K	298.15	PbO2-I. alloy: Pb 0.333333	experimental	[1] Risold 1998 cites Duisman 1968 doi	Table 1, p. 1, row 24 report
Entropy printed: S298	25.4667 J/mol-atom/K	298.15	PbO2-I. alloy: Pb 0.333333	unspecified	[1] Risold 1998 cites ref. 29Mil	Table 1, p. 1, row 23 report
Entropy printed: S298	23.9333 J/mol-atom/K	298.15	PbO2-I. alloy: Pb 0.333333	unspecified	[1] Risold 1998 cites Chase 1985	Table 1, p. 1, row 21 report
Entropy printed: ΔS	1.35 J/mol · K	762	PbO-L + PbO-M	model	[1] Risold 1998	Table 3, p. 3, row 4 report
Entropy printed: ΔS	0.79 J/mol · K	816	PbO-L + PbO-M	experimental	[1] Risold 1998 cites White 1961	Table 3, p. 3, row 5 report

Activity / EMF / Gibbs energy (2)

Activity / EMF / Gibbs energy, O–Pb system
Property	Value	T (K)	Phases / composition	Class	Source	Location	Quote
Vapour pressure printed: p(O2)	0.59 bar 02	515		experimental	[1] Risold 1998	p. 13 report	This evolution of oxygen was so slow that a precise value for the equilibrium oxygen pressure could not be obtained; however, it gives a limiting interval of 0.59 to 1.19 bar 02 at 515 K.
Vapour pressure printed: p(O2)	2 bar	653	Pb3Oa-T + Pb12017 + Pb]2019	experimental	[1] Risold 1998 cites White 1964	p. 12 report	The three phase Pb3Oa-T, Pb12017, and Pb]2019 have been predicted to be in equilibrium at about 653 K and 2 bar 02 based on the XRD analysis of annealed samples [64Whi, 65Roy].

Model expression (65)

Model expression, O–Pb system
Property	Value	Phases / composition	Class	Source	Location
gibbs energy expression term printed: ΔG0 constant term	-189851 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Taskinen 1979	Table 7, p. 6, row 38 report
gibbs energy expression term printed: ΔG0 coefficient of T	74.36 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Taskinen 1979	Table 7, p. 6, row 38 report
gibbs energy expression term printed: ΔG0 constant term	-191753 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Sridhar 1967	Table 7, p. 6, row 22 report
gibbs energy expression term printed: ΔG0 constant term	-188615 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charl 1976	Table 7, p. 6, row 33 report
gibbs energy expression term printed: ΔG0 constant term	-191350 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Sugawara 1977 doi	Table 7, p. 6, row 37 report
gibbs energy expression term printed: ΔG0 coefficient of T	74.6 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Sugawara 1977 doi	Table 7, p. 6, row 37 report
gibbs energy expression term printed: ΔG0 coefficient of T	74.91 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ICT 1971	Table 7, p. 6, row 24 report
gibbs energy expression term printed: ΔG0 constant term	-191008 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ICT 1971	Table 7, p. 6, row 24 report
gibbs energy expression term printed: ΔG0 constant term	-191209 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Kapoor 1973 doi	Table 7, p. 6, row 28 report
gibbs energy expression term printed: ΔG0 coefficient of T	73.64 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Kapoor 1973 doi	Table 7, p. 6, row 28 report
gibbs energy expression term printed: ΔG0 constant term	-180761 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Kapoor 1971 doi	Table 7, p. 6, row 25 report
gibbs energy expression term printed: ΔG0 coefficient of T	65.44 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Kapoor 1971 doi	Table 7, p. 6, row 25 report
gibbs energy expression term printed: ΔG0 coefficient of T	79.89 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Minenko 1963	Table 7, p. 6, row 20 report
gibbs energy expression term printed: ΔG0 constant term	-191093 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Minenko 1963	Table 7, p. 6, row 20 report
gibbs energy expression term printed: ΔG0 coefficient of T	94.14 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Perrot 1976	Table 7, p. 6, row 35 report
gibbs energy expression term printed: ΔG0 constant term	-214430 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Perrot 1976	Table 7, p. 6, row 35 report
gibbs energy expression term printed: ΔG0 coefficient of T	71.38 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 75Cal	Table 7, p. 6, row 30 report
gibbs energy expression term printed: ΔG0 constant term	-185891 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 75Cal	Table 7, p. 6, row 30 report
gibbs energy expression term printed: ΔG0 constant term	-190623 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Szware 1972	Table 7, p. 6, row 27 report
gibbs energy expression term printed: ΔG0 constant term	-184700 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Iwase 1975 doi	Table 7, p. 6, row 31 report
gibbs energy expression term printed: ΔG0 coefficient of T	70.92 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Iwase 1975 doi	Table 7, p. 6, row 31 report
gibbs energy expression term printed: ΔG0 constant term	-214430 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Codron 1972	Table 7, p. 6, row 26 report
gibbs energy expression term printed: ΔG0 coefficient of T	91.14 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Codron 1972	Table 7, p. 6, row 26 report
gibbs energy expression term printed: ΔG0 coefficient of T	69.45 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1973 doi	Table 7, p. 6, row 29 report
gibbs energy expression term printed: ΔG0 constant term	-185226 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1973 doi	Table 7, p. 6, row 29 report
gibbs energy expression term printed: ΔG0 coefficient of T	75.15 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charette 1968 doi	Table 7, p. 6, row 23 report
gibbs energy expression term printed: ΔG0 constant term	-190623 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charette 1968 doi	Table 7, p. 6, row 23 report
gibbs energy expression term printed: ΔG0 coefficient of T	81.3 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Suito 1976 doi	Table 7, p. 6, row 36 report
gibbs energy expression term printed: ΔG0 constant term	-194472 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Suito 1976 doi	Table 7, p. 6, row 36 report
gibbs energy expression term printed: ΔG0 coefficient of T	74.56 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Mat1	Table 7, p. 6, row 21 report
gibbs energy expression term printed: ΔG0 constant term	-191229 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Mat1	Table 7, p. 6, row 21 report
gibbs energy expression term printed: ΔG0 constant term	-189410 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1975	Table 7, p. 6, row 32 report
gibbs energy expression term printed: ΔG0 coefficient of T	72.63 J/mol/K	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1975	Table 7, p. 6, row 32 report
gibbs energy expression term printed: ΔG0 constant term	-189037 J/mol	PbO(liq) alloy: Pb 0.5	experimental	[1] Risold 1998 cites Leung 1976 doi	Table 7, p. 6, row 34 report
gibbs energy expression term printed: ΔG0 (T coefficient)	95.65 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 75Cal	Table 4, p. 4, row 21 report
gibbs energy expression term printed: ΔG0 (constant term)	-214660 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 75Cal	Table 4, p. 4, row 21 report
gibbs energy expression term printed: ΔG0 (constant term)	-218279 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1975	Table 4, p. 4, row 23 report
gibbs energy expression term printed: ΔG0 (T coefficient)	97.49 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1975	Table 4, p. 4, row 23 report
gibbs energy expression term printed: ΔG0 (T coefficient)	97.4 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Sugimoto 1980 doi	Table 4, p. 4, row 26 report
gibbs energy expression term printed: ΔG0 (constant term)	-216000 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Sugimoto 1980 doi	Table 4, p. 4, row 26 report
gibbs energy expression term printed: ΔG0 (constant term)	-220010 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 84Ban	Table 4, p. 4, row 27 report
gibbs energy expression term printed: ΔG0 (T coefficient)	100.91 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 84Ban	Table 4, p. 4, row 27 report
gibbs energy expression term printed: ΔG0 (constant term)	-218099 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ICT 1971	Table 4, p. 4, row 18 report
gibbs energy expression term printed: ΔG0 (T coefficient)	98.89 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ICT 1971	Table 4, p. 4, row 18 report
gibbs energy expression term printed: ΔG0 (T coefficient)	92.54 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mallika 1995	Table 4, p. 4, row 28 report
gibbs energy expression term printed: ΔG0 (constant term)	-212640 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mallika 1995	Table 4, p. 4, row 28 report
gibbs energy expression term printed: ΔG0 (T coefficient)	96.39 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charette 1968 doi	Table 4, p. 4, row 17 report
gibbs energy expression term printed: ΔG0 (constant term)	-215058 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charette 1968 doi	Table 4, p. 4, row 17 report
gibbs energy expression term printed: ΔG0 (constant term)	-215231 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Taskinen 1979	Table 4, p. 4, row 25 report
gibbs energy expression term printed: ΔG0 (T coefficient)	96.54 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Taskinen 1979	Table 4, p. 4, row 25 report
gibbs energy expression term printed: ΔG0 (constant term)	-219367 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Alc	Table 4, p. 4, row 15 report
gibbs energy expression term printed: ΔG0 (T coefficient)	100.92 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Alc	Table 4, p. 4, row 15 report
gibbs energy expression term printed: ΔG0 (T coefficient)	97.28 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Iwase 1975 doi	Table 4, p. 4, row 22 report
gibbs energy expression term printed: ΔG0 (constant term)	-215000 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Iwase 1975 doi	Table 4, p. 4, row 22 report
gibbs energy expression term printed: ΔG0 (constant term)	-215058 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Szware 1972	Table 4, p. 4, row 19 report
gibbs energy expression term printed: ΔG0 (T coefficient)	96.23 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Szware 1972	Table 4, p. 4, row 19 report
gibbs energy expression term printed: ΔG0 (T coefficient)	98.03 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charl 1976	Table 4, p. 4, row 24 report
gibbs energy expression term printed: ΔG0 (constant term)	-216606 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Charl 1976	Table 4, p. 4, row 24 report
gibbs energy expression term printed: ΔG0 (T coefficient)	94.14 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1973 doi	Table 4, p. 4, row 20 report
gibbs energy expression term printed: ΔG0 (constant term)	-214095 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites Mehrotra 1973 doi	Table 4, p. 4, row 20 report
gibbs energy expression term printed: ΔG0 (constant term)	-218059 J/mol	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Mat1	Table 4, p. 4, row 16 report
gibbs energy expression term printed: ΔG0 (T coefficient)	98.2 J/mol/K	UNKNOWN alloy: Pb 0.5	experimental	[1] Risold 1998 cites ref. 64Mat1	Table 4, p. 4, row 16 report
gm form expression term printed: ΔfG298 (a)	-94.659 kJ/mol-atom	PbO-L alloy: Pb 0.5	experimental	[1] Risold 1998 cites Spencer 1932 doi	Table 1, p. 1, row 4 report
gm form expression term printed: ΔfG298 (a)	-94.3555 kJ/mol-atom	PbO-M alloy: Pb 0.5	experimental	[1] Risold 1998 cites Spencer 1932 doi	Table 1, p. 1, row 9 report
gm form expression term printed: ΔfG298 (a)	-72.983 kJ/mol-atom	PbO2-I alloy: Pb 0.333333	unspecified	[1] Risold 1998 cites ref. 29Mil	Table 1, p. 1, row 23 report

Sources

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

D. Risold, J. -I. Nagata, R. O. Suzuki, Thermodynamic description of the Pb-O system, JPE 19, 213-233 (1998). doi:10.1361/105497198770342238

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}
}