Ba–Pb phases

11 phases (tier A 6, tier C 2, liquid 1, needs_review 2); 10 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: interactive registry · full JSON · Ba–Pb system page · Markdown · field reference

Phases of the Ba–Pb system (11)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BA17PB23 phase:ba-pb:ba17pb23		needs_review	stable in 1 of 1 calculated diagram(s): 300–1110.87 K, x(Pb) 0.575–0.575	8	1
BA2PB_C37 phase:ba-pb:ba2pb-c37	Co2Si · C37 · oP12 · Pnma (62)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1184.64 K, x(Pb) 0.33333–0.33333	8	1
BA3PB5_HT phase:ba-pb:ba3pb5-ht		needs_review	stable in 1 of 1 calculated diagram(s): 977.58–986.14 K, x(Pb) 0.625–0.625	11	1
BA3PB5_LT phase:ba-pb:ba3pb5-lt	Pd5Pu3 · oC32 · Cmcm (63)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–977.58 K, x(Pb) 0.625–0.625	13	1
BA5PB3_D8L phase:ba-pb:ba5pb3-d8l	Cr5B3 · D8_l · tI32 · I4/mcm (140)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1243.81 K, x(Pb) 0.375–0.375	12	1
BAPB_B33 phase:ba-pb:bapb-b33	CrB · B33 · oC8 · Cmcm (63)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1126.91 K, x(Pb) 0.5–0.5	12	1
BAPB3 phase:ba-pb:bapb3	BaPb3 · hR12 · R-3m (166)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–870.28 K, x(Pb) 0.75–0.75	11	1
BCC_A2 phase:ba-pb:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1004 K, x(Pb) 0–0.00133	3	1
FCC_A1 phase:ba-pb:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–601.61 K, x(Pb) 0.99184–1	2	1
HCP_A3 phase:ba-pb:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
LIQUID phase:ba-pb:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 563.12–2500 K, x(Pb) 0–1	43	1

BA17PB23 (Ba–Pb)

Id: phase:ba-pb:ba17pb23; status needs_review
No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
Candidate (literature_printed): (Ba17Pb23) · ? — printed with a label mapped to this phase
Candidate (sgte_mmc2): (Ba17Pb23) — Hallstedt 2025 mmc2 row for BA17PB23: Ba17Pb23
Stoichiometry: Ba 0.4250, Pb 0.5750
Stability: stable in 1 of 1 calculated diagram(s): 300–1110.87 K, x(Pb) 0.575–0.575
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:ba17pb23
paper: paper:10.1016/j.calphad.2007.04.003:Ba0.425Pb0.575
tdb: tdb:BaPb-07Idb.tdb:BA17PB23

TDB models of BA17PB23 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BA17PB23, type code %, sha256 faf589a587c1792e…

68: PHASE BA17PB23 % 2 17 23 !
69: CONST BA17PB23 : BA : PB : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase

BA2PB_C37 (Ba–Pb)

Id: phase:ba-pb:ba2pb-c37; status assigned
Structure: Co2Si · C37 · oP12 · Pnma (62); type st:c37-co2si-op12; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaabfle and oqmd-10855, space group 62
Stoichiometry: Ba 0.6667, Pb 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–1184.64 K, x(Pb) 0.33333–0.33333
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:ba-pb:ba2pb-c37
mp: mp:mp-aaaabfle
oqmd: oqmd:oqmd-10855
paper: paper:10.1016/j.calphad.2007.04.003:Ba2Pb
tdb: tdb:BaPb-07Idb.tdb:BA2PB_C37

TDB models of BA2PB_C37 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BA2PB_C37, type code %, sha256 faf589a587c1792e…

53: PHASE BA2PB_C37 % 2 2 1 !
54: CONST BA2PB_C37 : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BA3PB5_HT (Ba–Pb)

Id: phase:ba-pb:ba3pb5-ht; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition; sgte_mmc2_row_incomplete
Candidate (dft_mp): Cmcm (63) — on-hull MP Ba3Pb5 at x(PB)=0.6250
Candidate (dft_oqmd): Cmcm (63) — on-hull OQMD Ba3 Pb5 at x(PB)=0.6250
Candidate (literature_printed): (Ba3Pb5) · ? — printed with a label mapped to this phase
Candidate (sgte_mmc2): (Ba3Pb5) — Hallstedt 2025 mmc2 row for BA3PB5_HT: Ba3Pb5 (high T)
Stoichiometry: Ba 0.3750, Pb 0.6250
Stability: stable in 1 of 1 calculated diagram(s): 977.58–986.14 K, x(Pb) 0.625–0.625
Literature: 11 values (11 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:ba3pb5-ht
paper: paper:10.1016/j.calphad.2007.04.003:βBa3Pb5
tdb: tdb:BaPb-07Idb.tdb:BA3PB5_HT

TDB models of BA3PB5_HT (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BA3PB5_HT, type code %, sha256 faf589a587c1792e…

78: PHASE BA3PB5_HT % 2 3 5 !
79: CONST BA3PB5_HT : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BA3PB5_LT (Ba–Pb)

Id: phase:ba-pb:ba3pb5-lt; status assigned
Structure: Pd5Pu3 · oC32 · Cmcm (63); type st:pd5pu3-oc32; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (no_structure_token, polymorph_family:other phases of this system have the same composition); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Ba 0.3750, Pb 0.6250
Stability: stable in 1 of 1 calculated diagram(s): 300–977.58 K, x(Pb) 0.625–0.625
Literature: 13 values (13 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:ba3pb5-lt
paper: paper:10.1016/j.calphad.2007.04.003:αBa3Pb5
tdb: tdb:BaPb-07Idb.tdb:BA3PB5_LT

TDB models of BA3PB5_LT (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BA3PB5_LT, type code %, sha256 faf589a587c1792e…

73: PHASE BA3PB5_LT % 2 3 5 !
74: CONST BA3PB5_LT : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BA5PB3_D8L (Ba–Pb)

Id: phase:ba-pb:ba5pb3-d8l; status assigned
Structure: Cr5B3 · D8_l · tI32 · I4/mcm (140); type st:d8-l-cr5b3-ti32; tier A: standard phase name; confidence high
Stoichiometry: Ba 0.6250, Pb 0.3750
Stability: stable in 1 of 1 calculated diagram(s): 300–1243.81 K, x(Pb) 0.375–0.375
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:ba5pb3-d8l
paper: paper:10.1016/j.calphad.2007.04.003:Ba5Pb3
tdb: tdb:BaPb-07Idb.tdb:BA5PB3_D8L

TDB models of BA5PB3_D8L (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BA5PB3_D8L, type code %, sha256 faf589a587c1792e…

58: PHASE BA5PB3_D8L % 2 5 3 !
59: CONST BA5PB3_D8L : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BAPB_B33 (Ba–Pb)

Id: phase:ba-pb:bapb-b33; status assigned
Structure: CrB · B33 · oC8 · Cmcm (63); type st:b33-crb-oc8; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaabdum and oqmd-10853, space group 63
Stoichiometry: Ba 0.5000, Pb 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–1126.91 K, x(Pb) 0.5–0.5
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:ba-pb:bapb-b33
mp: mp:mp-aaaabdum
oqmd: oqmd:oqmd-10853
paper: paper:10.1016/j.calphad.2007.04.003:BaPb
tdb: tdb:BaPb-07Idb.tdb:BAPB_B33

TDB models of BAPB_B33 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BAPB_B33, type code %, sha256 faf589a587c1792e…

63: PHASE BAPB_B33 % 2 1 1 !
64: CONST BAPB_B33 : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BAPB3 (Ba–Pb)

Id: phase:ba-pb:bapb3; status assigned
Structure: BaPb3 · hR12 · R-3m (166); type st:bapb3-hr12; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (dft_space_group_166_matches_2_structure_types, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Ba 0.2500, Pb 0.7500
Stability: stable in 1 of 1 calculated diagram(s): 300–870.28 K, x(Pb) 0.75–0.75
Literature: 11 values (11 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:bapb3
paper: paper:10.1016/j.calphad.2007.04.003:BaPb3
tdb: tdb:BaPb-07Idb.tdb:BAPB3

TDB models of BAPB3 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BAPB3, type code %, sha256 faf589a587c1792e…

83: PHASE BAPB3 % 2 1 3 !
84: CONST BAPB3 : BA : PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

BCC_A2 (Ba–Pb)

Id: phase:ba-pb:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–1004 K, x(Pb) 0–0.00133
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:bcc-a2
paper: paper:10.1016/j.calphad.2007.04.003:(Ba)
tdb: tdb:BaPb-07Idb.tdb:BCC_A2

TDB models of BCC_A2 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: BCC_A2, type code %B, sha256 faf589a587c1792e…

43: PHASE BCC_A2 %B 2 1 3 !
44: CONST BCC_A2 : BA% PB : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase

FCC_A1 (Ba–Pb)

Id: phase:ba-pb:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–601.61 K, x(Pb) 0.99184–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:fcc-a1
paper: paper:10.1016/j.calphad.2007.04.003:(Pb)
tdb: tdb:BaPb-07Idb.tdb:FCC_A1

TDB models of FCC_A1 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: FCC_A1, type code %A, sha256 faf589a587c1792e…

38: PHASE FCC_A1 %A 2 1 1 !
39: CONST FCC_A1 : BA PB% : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

HCP_A3 (Ba–Pb)

Id: phase:ba-pb:hcp-a3; status assigned
Structure: Mg · A3 · hP2 · P6_3/mmc (194); type st:a3-mg-hp2; tier A: standard phase name; confidence high
Stability: not stable in 1 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ba-pb:hcp-a3
tdb: tdb:BaPb-07Idb.tdb:HCP_A3

TDB models of HCP_A3 (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: HCP_A3, type code %A, sha256 faf589a587c1792e…

48: PHASE HCP_A3 %A 2 1 0.5 !
49: CONST HCP_A3 : BA PB : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase

LIQUID (Ba–Pb)

Id: phase:ba-pb:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 563.12–2500 K, x(Pb) 0–1
Literature: 43 values (43 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ba-pb:liquid
paper: paper:10.1016/j.calphad.2007.04.003:Liq
tdb: tdb:BaPb-07Idb.tdb:LIQUID

TDB models of LIQUID (1): PHASE and CONSTITUENT statements as written

BaPb-07Idb.tdb: LIQUID, type code %, sha256 faf589a587c1792e…

33: PHASE LIQUID:L % 1 1 !
34: CONST LIQUID:L : BA BAPB PB : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2007.04.003 M. Idbenali, C. Servant, N. Selhaoui, L. Bouirden, A thermodynamic modelling of the Ba–Pb system, Calphad 31, 479-489 (2007).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(77)90003-0 Giacomo Bruzzone, Enrico Franceschi, Equilibrium phase diagram and crystal structures of the intermediate phases of the Ba-Pb binary system, Journal of the Less Common Metals 52, 211-216 (1977).
cited as the source of values for this phase

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Registry: phase registry of binary systems (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735970
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 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); the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work). 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_phase_registry_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Registry: phase registry of binary systems}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735970},
  url       = {https://doi.org/10.5281/zenodo.23735970},
  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}
}