Bi–Pd phases

9 phases (tier A 4, liquid 1, needs_review 4); 7 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 · Bi–Pd system page · Markdown · field reference

Phases of the Bi–Pd system (9)
Phase	Structure	Basis	Stability (calculated)	TDB models
RHOMBOHEDRAL_A7 phase:bi-pd:a7-rhombohedral	alpha-As · A7 · hR2 · R-3m (166)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–544.55 K, x(Pd) 0–4e-05	1
BCC_A2 phase:bi-pd:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
BI2PD phase:bi-pd:bi2pd		needs_review	stable in 1 of 1 calculated diagram(s): 300–786.95 K, x(Pd) 0.33333–0.33333	1
BI3PD5 phase:bi-pd:bi3pd5		needs_review	stable in 1 of 1 calculated diagram(s): 558.55–958.09 K, x(Pd) 0.62948–0.66635	1
BIPD phase:bi-pd:bipd		needs_review	stable in 1 of 1 calculated diagram(s): 300–895.92 K, x(Pd) 0.5–0.5	1
BIPD3 phase:bi-pd:bipd3		needs_review	stable in 1 of 1 calculated diagram(s): 300–1204.58 K, x(Pd) 0.75–0.75	1
FCC_A1 phase:bi-pd:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2353 K, x(Pd) 0.81874–1	1
HCP_A3 phase:bi-pd:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
LIQUID phase:bi-pd:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 518.05–2500 K, x(Pd) 0–1	1

RHOMBOHEDRAL_A7 (Bi–Pd)

Id: phase:bi-pd:a7-rhombohedral; status assigned
Structure: alpha-As · A7 · hR2 · R-3m (166); type st:a7-alpha-as-hr2; tier A: standard phase name; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–544.55 K, x(Pd) 0–4e-05
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:a7-rhombohedral
tdb: tdb:BiPd-06Vre-LB.tdb:RHOMBOHEDRAL_A7

TDB models of RHOMBOHEDRAL_A7 (1): PHASE and CONSTITUENT statements as written

BiPd-06Vre-LB.tdb: RHOMBOHEDRAL_A7, type code %, sha256 fa44884f406f91f1…

45: PHASE RHOMBOHEDRAL_A7 % 1 1 !
46: CONST RHOMBOHEDRAL_A7 : BI% PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

BCC_A2 (Bi–Pd)

Id: phase:bi-pd:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stoichiometry: Pd 1.0000
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:bi-pd:bcc-a2
tdb: tdb:BiPd-06Vre-LB.tdb:BCC_A2

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

BiPd-06Vre-LB.tdb: BCC_A2, type code %, sha256 fa44884f406f91f1…

35: PHASE BCC_A2 % 2 1 3 !
36: CONST BCC_A2 : PD : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

BI2PD (Bi–Pd)

Id: phase:bi-pd:bi2pd; status needs_review
No structure assigned. Why: mp_oqmd_space_groups_differ; no_structure_token; sgte_mmc2_rows_disagree
Candidate (dft_mp): C2/m (12) — on-hull MP Bi2Pd at x(PD)=0.3333
Candidate (dft_oqmd): Fm-3m (225) — on-hull OQMD Bi2 Pd1 at x(PD)=0.3333
Candidate (sgte_mmc2): alpha-Bi2Pd · mC12 · C2/m (12) — Hallstedt 2025 mmc2 row for BI2PD: Bi2Pd (alpha), see also CuZr2
Candidate (sgte_mmc2): CuZr2 · tI6 · I4/mmm (139) — Hallstedt 2025 mmc2 row for BI2PD: Bi2Pd (beta), see also alpha-Bi2Pd
Candidate (tdb_comment): alpha-Bi2Pd · mC12 · C2/m — BiPd-06Vre-LB.tdb: 'Prototype alpha-Bi2Pd (mC12, C2/m) and CuZr2 (tI6, I4/mmm), beta'
Stoichiometry: Bi 0.6667, Pd 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–786.95 K, x(Pd) 0.33333–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:bi2pd
tdb: tdb:BiPd-06Vre-LB.tdb:BI2PD

TDB models of BI2PD (1): PHASE and CONSTITUENT statements as written

BiPd-06Vre-LB.tdb: BI2PD, type code %, sha256 fa44884f406f91f1…

50: PHASE BI2PD % 2 2 1 !
51: CONST BI2PD : BI : PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

BI3PD5 (Bi–Pd)

Id: phase:bi-pd:bi3pd5; status needs_review
No structure assigned. Why: no_structure_token; off_stoichiometric_model; sgte_mmc2_row_incomplete
Candidate (sgte_mmc2): (Bi3Pd5) · hP16 — Hallstedt 2025 mmc2 row for BI3PD5: Bi3Pd5 (NiAs superstructure)
Stability: stable in 1 of 1 calculated diagram(s): 558.55–958.09 K, x(Pd) 0.62948–0.66635
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:bi3pd5
tdb: tdb:BiPd-06Vre-LB.tdb:BI3PD5

TDB models of BI3PD5 (1): PHASE and CONSTITUENT statements as written

BiPd-06Vre-LB.tdb: BI3PD5, type code %, sha256 fa44884f406f91f1…

60: PHASE BI3PD5 % 1 1 !
61: CONST BI3PD5 : BI PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

BIPD (Bi–Pd)

Id: phase:bi-pd:bipd; status needs_review
No structure assigned. Why: dft_space_group_194_matches_2_structure_types; no_structure_token; sgte_mmc2_row_disagrees_with_dft; sgte_mmc2_rows_disagree
Candidate (dft_mp): P6_3/mmc (194) — on-hull MP BiPd at x(PD)=0.5000
Candidate (dft_oqmd): P63/mmc (194) — on-hull OQMD Bi1 Pd1 at x(PD)=0.5000
Candidate (dft_space_group_and_stoichiometry): BN · B_k · hP4 · P6_3/mmc (194) — space group 194 and stoichiometry match
Candidate (dft_space_group_and_stoichiometry): NiAs · B8_1 · hP4 · P6_3/mmc (194) — space group 194 and stoichiometry match
Candidate (sgte_mmc2): alpha-BiPd · mP16 · P2_1 (4) — Hallstedt 2025 mmc2 row for BIPD: BiPd (alpha)
Candidate (sgte_mmc2): beta-BiPd · oC32 · Cmc2_1 (36) — Hallstedt 2025 mmc2 row for BIPD: BiPd (beta)
Candidate (tdb_comment): alpha-BiPd · mP16 · P2_1 — BiPd-06Vre-LB.tdb: 'Prototype alpha-BiPd (mP16, P2_1) and beta-BiPd (oC32, Cmc2_1)'
Stoichiometry: Bi 0.5000, Pd 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–895.92 K, x(Pd) 0.5–0.5
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:bipd
tdb: tdb:BiPd-06Vre-LB.tdb:BIPD

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

BiPd-06Vre-LB.tdb: BIPD, type code %, sha256 fa44884f406f91f1…

55: PHASE BIPD % 2 1 1 !
56: CONST BIPD : BI : PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

BIPD3 (Bi–Pd)

Id: phase:bi-pd:bipd3; status needs_review
No structure assigned. Why: mp_oqmd_space_groups_differ; no_structure_token; sgte_mmc2_rows_disagree
Candidate (dft_mp): Pmma (51) — on-hull MP BiPd3 at x(PD)=0.7500
Candidate (dft_oqmd): Pmmn (59) — on-hull OQMD Bi1 Pd3 at x(PD)=0.7500
Candidate (sgte_mmc2): alpha-BiPd3 · oP16 · Pmma (51) — Hallstedt 2025 mmc2 row for BIPD3: BiPd3 (alpha)
Candidate (sgte_mmc2): (beta-BiPd3) — Hallstedt 2025 mmc2 row for BIPD3: BiPd3 (beta)
Candidate (tdb_comment): alpha-BiPd3 · oP16 · Pmma — BiPd-06Vre-LB.tdb: 'Prototype alpha-BiPd3 (oP16, Pmma) and unknown structure, beta'
Stoichiometry: Bi 0.2500, Pd 0.7500
Stability: stable in 1 of 1 calculated diagram(s): 300–1204.58 K, x(Pd) 0.75–0.75
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:bipd3
tdb: tdb:BiPd-06Vre-LB.tdb:BIPD3

TDB models of BIPD3 (1): PHASE and CONSTITUENT statements as written

BiPd-06Vre-LB.tdb: BIPD3, type code %, sha256 fa44884f406f91f1…

65: PHASE BIPD3 % 2 1 3 !
66: CONST BIPD3 : BI : PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

FCC_A1 (Bi–Pd)

Id: phase:bi-pd: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): 300–2353 K, x(Pd) 0.81874–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:fcc-a1
tdb: tdb:BiPd-06Vre-LB.tdb:FCC_A1

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

BiPd-06Vre-LB.tdb: FCC_A1, type code %, sha256 fa44884f406f91f1…

30: PHASE FCC_A1 % 2 1 1 !
31: CONST FCC_A1 : BI PD% : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

HCP_A3 (Bi–Pd)

Id: phase:bi-pd:hcp-a3; status assigned
Structure: Mg · A3 · hP2 · P6_3/mmc (194); type st:a3-mg-hp2; tier A: standard phase name; confidence high
Stoichiometry: Pd 1.0000
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:bi-pd:hcp-a3
tdb: tdb:BiPd-06Vre-LB.tdb:HCP_A3

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

BiPd-06Vre-LB.tdb: HCP_A3, type code %, sha256 fa44884f406f91f1…

40: PHASE HCP_A3 % 2 1 0.5 !
41: CONST HCP_A3 : PD : VA: !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
assessment that models this phase

LIQUID (Bi–Pd)

Id: phase:bi-pd:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 518.05–2500 K, x(Pd) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-pd:liquid
tdb: tdb:BiPd-06Vre-LB.tdb:LIQUID

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

BiPd-06Vre-LB.tdb: LIQUID, type code %, sha256 fa44884f406f91f1…

25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : BI PD : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.12.001 J. Vřešt’ál, J. Pinkas, A. Watson, A. Scott, J. Houserová, A. Kroupa, Assessment of the thermodynamic properties and phase diagram of the Bi–Pd system, Calphad 30, 14-17 (2006).
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}
}