Pb–Sn phases

6 phases (tier A 5, liquid 1); 4 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 · Pb–Sn system page · Markdown · field reference

Phases of the Pb–Sn system (6)
Phase	Structure	Basis	Stability (calculated)	TDB models
DIAMOND_A4 phase:pb-sn:a4-diamond	C (diamond) · A4 · cF8 · Fd-3m (227)	tier A: standard phase name	stable in 1 of 3 calculated diagram(s): 300–300 K	3
BCT_A5 phase:pb-sn:a5-bct	beta-Sn · A5 · tI4 · I4_1/amd (141)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–505.08 K, x(Sn) 0.97537–1	3
BCC_A2 phase:pb-sn:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 2 calculated diagram(s)	2
FCC_A1 phase:pb-sn:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 3 of 3 calculated diagram(s): 300–600.61 K, x(Sn) 0–0.30618	3
HCP_A3 phase:pb-sn:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 3 calculated diagram(s)	3
LIQUID phase:pb-sn:liquid	liquid	liquid	stable in 3 of 3 calculated diagram(s): 455.69–2500 K, x(Sn) 0–1	3

DIAMOND_A4 (Pb–Sn)

Id: phase:pb-sn:a4-diamond; status assigned
Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type st:a4-c-diamond-cf8; tier A: standard phase name; confidence high
Stoichiometry: Sn 1.0000
Stability: stable in 1 of 3 calculated diagram(s): 300–300 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:pb-sn:a4-diamond
tdb: tdb:PbSn-17Gie.tdb:DIAMOND_A4, tdb:PbSn-22Khv-3g.tdb:DIAMOND_A4, tdb:PbSn-95Oht-LB.tdb:DIAMOND_A4

TDB models of DIAMOND_A4 (3): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: DIAMOND_A4, type code %, sha256 7a442ed9f5eb5e7a…

41: PHASE DIAMOND_A4 % 1 1 !
42: CONST DIAMOND_A4 : SN : !

PbSn-22Khv-3g.tdb: DIAMOND_A4, type code %, sha256 cc698ce94556d47f…

52: PHASE DIAMOND_A4 % 1 1 !
53: CONST DIAMOND_A4 : SN : !

PbSn-95Oht-LB.tdb: DIAMOND_A4, type code %, sha256 04c045f1bd0a9b7e…

57: PHASE DIAMOND_A4 % 1 1 !
58: CONST DIAMOND_A4 : SN : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2022.102396 A.V. Khvan, A.T. Dinsdale, Q. Chen, Calphad, 76, 102396(2022).
assessment that models this phase

BCT_A5 (Pb–Sn)

Id: phase:pb-sn:a5-bct; status assigned
Structure: beta-Sn · A5 · tI4 · I4_1/amd (141); type st:a5-beta-sn-ti4; tier A: standard phase name; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 300–505.08 K, x(Sn) 0.97537–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:pb-sn:a5-bct
tdb: tdb:PbSn-17Gie.tdb:BCT_A5, tdb:PbSn-22Khv-3g.tdb:BCT_A5, tdb:PbSn-95Oht-LB.tdb:BCT_A5

TDB models of BCT_A5 (3): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: BCT_A5, type code %, sha256 7a442ed9f5eb5e7a…

46: PHASE BCT_A5 % 1 1 !
47: CONST BCT_A5 : PB SN% : !

PbSn-22Khv-3g.tdb: BCT_A5, type code %, sha256 cc698ce94556d47f…

57: PHASE BCT_A5 % 1 1.545977367 !
58: CONST BCT_A5 : PB SN% : !

PbSn-95Oht-LB.tdb: BCT_A5, type code %, sha256 04c045f1bd0a9b7e…

62: PHASE BCT_A5 % 1 1 !
63: CONST BCT_A5 : PB SN% : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2022.102396 A.V. Khvan, A.T. Dinsdale, Q. Chen, Calphad, 76, 102396(2022).
assessment that models this phase

BCC_A2 (Pb–Sn)

Id: phase:pb-sn:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: not stable in 2 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:pb-sn:bcc-a2
tdb: tdb:PbSn-17Gie.tdb:BCC_A2, tdb:PbSn-95Oht-LB.tdb:BCC_A2

TDB models of BCC_A2 (2): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: BCC_A2, type code %B, sha256 7a442ed9f5eb5e7a…

31: PHASE BCC_A2 %B 2 1 3 !
32: CONST BCC_A2 : PB SN : VA : !

PbSn-95Oht-LB.tdb: BCC_A2, type code %B, sha256 04c045f1bd0a9b7e…

47: PHASE BCC_A2 %B 2 1 3 !
48: CONST BCC_A2 : PB SN : VA : !

Example references (2 of 2; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase

FCC_A1 (Pb–Sn)

Id: phase:pb-sn: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 3 of 3 calculated diagram(s): 300–600.61 K, x(Sn) 0–0.30618
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:pb-sn:fcc-a1
tdb: tdb:PbSn-17Gie.tdb:FCC_A1, tdb:PbSn-22Khv-3g.tdb:FCC_A1, tdb:PbSn-95Oht-LB.tdb:FCC_A1

TDB models of FCC_A1 (3): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: FCC_A1, type code %A, sha256 7a442ed9f5eb5e7a…

26: PHASE FCC_A1 %A 2 1 1 !
27: CONST FCC_A1 : PB% SN : VA : !

PbSn-22Khv-3g.tdb: FCC_A1, type code %A, sha256 cc698ce94556d47f…

37: PHASE FCC_A1 %A 2 1 1 !
38: CONST FCC_A1 : PB% SN : VA : !

PbSn-95Oht-LB.tdb: FCC_A1, type code %A, sha256 04c045f1bd0a9b7e…

42: PHASE FCC_A1 %A 2 1 1 !
43: CONST FCC_A1 : PB% SN : VA : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2022.102396 A.V. Khvan, A.T. Dinsdale, Q. Chen, Calphad, 76, 102396(2022).
assessment that models this phase

HCP_A3 (Pb–Sn)

Id: phase:pb-sn: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 3 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:pb-sn:hcp-a3
tdb: tdb:PbSn-17Gie.tdb:HCP_A3, tdb:PbSn-22Khv-3g.tdb:HCP_A3, tdb:PbSn-95Oht-LB.tdb:HCP_A3

TDB models of HCP_A3 (3): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: HCP_A3, type code %A, sha256 7a442ed9f5eb5e7a…

36: PHASE HCP_A3 %A 2 1 0.5 !
37: CONST HCP_A3 : PB SN : VA : !

PbSn-22Khv-3g.tdb: HCP_A3, type code %A, sha256 cc698ce94556d47f…

47: PHASE HCP_A3 %A 2 1 0.5 !
48: CONST HCP_A3 : PB SN : VA : !

PbSn-95Oht-LB.tdb: HCP_A3, type code %A, sha256 04c045f1bd0a9b7e…

52: PHASE HCP_A3 %A 2 1 0.5 !
53: CONST HCP_A3 : PB SN : VA : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2022.102396 A.V. Khvan, A.T. Dinsdale, Q. Chen, Calphad, 76, 102396(2022).
assessment that models this phase

LIQUID (Pb–Sn)

Id: phase:pb-sn:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 3 of 3 calculated diagram(s): 455.69–2500 K, x(Sn) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:pb-sn:liquid
tdb: tdb:PbSn-17Gie.tdb:LIQUID, tdb:PbSn-22Khv-3g.tdb:LIQUID, tdb:PbSn-95Oht-LB.tdb:LIQUID

TDB models of LIQUID (3): PHASE and CONSTITUENT statements as written

PbSn-17Gie.tdb: LIQUID, type code %, sha256 7a442ed9f5eb5e7a…

21: PHASE LIQUID:L % 1 1 !
22: CONST LIQUID:L : PB SN : !

PbSn-22Khv-3g.tdb: LIQUID, type code %, sha256 cc698ce94556d47f…

32: PHASE LIQUID:L % 1 1 !
33: CONST LIQUID:L : PB SN : !

PbSn-95Oht-LB.tdb: LIQUID, type code %, sha256 04c045f1bd0a9b7e…

37: PHASE LIQUID:L % 1 1 !
38: CONST LIQUID:L : PB SN : !

Example references (3 of 3; assessments first):

doi:10.1007/BF02645349 H. Ohtani, K. Okuda, K. Ishida, J. Phase Equilib., 16, 416-29(1995).
assessment that models this phase
doi:10.1007/s11669-017-0572-5 Wojciech Gierlotka, Yi-Cheng Tung, A New Thermodynamic Description of the Bi-Pb-Sn System, J. Phase Equilib. Diffus. 38, 814-828 (2017).
assessment that models this phase
doi:10.1016/j.calphad.2022.102396 A.V. Khvan, A.T. Dinsdale, Q. Chen, Calphad, 76, 102396(2022).
assessment that models 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}
}