# Bi–Pd phases > Bi–Pd system: 9 phases (tier A 4, liquid 1, needs_review 4); 7 stable in a calculated diagram in the ORCHID phase registry, with names, structure type when the stored evidence supports an assignment under the stated tier rules, calculated stability, verbatim TDB PHASE/CONSTITUENT statements and example references. HTML: https://data.orchid-project.org/phases/pages/BI-PD.html · Markdown: https://data.orchid-project.org/phases/pages/BI-PD.md 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](https://orchid-project.org/phases/?q=BI-PD) · [full JSON](https://data.orchid-project.org/phases/systems/BI-PD.json) · [Bi–Pd system page](https://data.orchid-project.org/systems/BI-PD.html) · [Markdown](https://data.orchid-project.org/phases/pages/BI-PD.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md) Table: Phases of the Bi–Pd system (9) | Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models | |---|---|---|---|---:|---:| | [RHOMBOHEDRAL_A7](#phase-bi-pd-a7-rhombohedral); _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 | 0 | 1 | | [BCC_A2](#phase-bi-pd-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) | 0 | 1 | | [BI2PD](#phase-bi-pd-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 | 0 | 1 | | [BI3PD5](#phase-bi-pd-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 | 0 | 1 | | [BIPD](#phase-bi-pd-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 | 0 | 1 | | [BIPD3](#phase-bi-pd-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 | 0 | 1 | | [FCC_A1](#phase-bi-pd-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 | 0 | 1 | | [HCP_A3](#phase-bi-pd-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) | 0 | 1 | | [LIQUID](#phase-bi-pd-liquid); _phase:bi-pd:liquid_ | liquid | liquid | stable in 1 of 1 calculated diagram(s): 518.05–2500 K, x(Pd) 0–1 | 0 | 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](https://orchid-project.org/phases/#phase:bi-pd:a7-rhombohedral) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): RHOMBOHEDRAL_A7, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:bcc-a2) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): BCC_A2, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:bi2pd) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): BI2PD, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:bi3pd5) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): BI3PD5, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:bipd) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): BIPD, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:bipd3) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): BIPD3, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:fcc-a1) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): FCC_A1, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:hcp-a3) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): HCP_A3, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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](https://orchid-project.org/phases/#phase:bi-pd:liquid) 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](https://orchid-project.org/data/databases/sgte-binary/BiPd-06Vre-LB.tdb): LIQUID, type code %, sha256 `fa44884f406f91f1…` ~~~~text 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](https://doi.org/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). https://doi.org/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). https://doi.org/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. ```bibtex @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} } ``` --- Derived data CC BY 4.0 ([licence](https://creativecommons.org/licenses/by/4.0/)): cite the ORCHID phase registry and the sources named on the page (TDB assessments, Hallstedt 2025, Materials Project, OQMD). TDB statements are quoted as written; parameter expressions are not reproduced. Field reference: [SCHEMA.md](https://data.orchid-project.org/phases/SCHEMA.md). Machine-readable guide: [llms.txt](https://data.orchid-project.org/llms.txt).