# Al–Pd phases

> Al–Pd system: 13 phases (tier A 7, tier B 1, tier C 2, liquid 1, needs_review 2); 11 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/AL-PD.html · Markdown: https://data.orchid-project.org/phases/pages/AL-PD.md

13 phases (tier A 7, tier B 1, tier C 2, liquid 1, needs_review 2); 11 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=AL-PD) · [full JSON](https://data.orchid-project.org/phases/systems/AL-PD.json) · [Al–Pd system page](https://data.orchid-project.org/systems/AL-PD.html) · [Markdown](https://data.orchid-project.org/phases/pages/AL-PD.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the Al–Pd system (13)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [AL21PD8](#phase-al-pd-al21pd8); _phase:al-pd:al21pd8_ | Al21Pt8 · tI116 · I4_1/a (88) | tier B: DFT-supported (unique MP + OQMD match) | stable in 3 of 3 calculated diagram(s): 300–1063.8 K, x(Pd) 0.27586–0.27586 | 6 | 3 |
| [AL2PD5](#phase-al-pd-al2pd5); _phase:al-pd:al2pd5_ | Ga2Pd5 · oP28 · Pnma (62) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 3 of 3 calculated diagram(s): 300–1246.17 K, x(Pd) 0.70404–0.71429 | 4 | 3 |
| [AL3PD](#phase-al-pd-al3pd); _phase:al-pd:al3pd_ |  | needs_review | stable in 3 of 3 calculated diagram(s): 852.09–1059.13 K, x(Pd) 0.25–0.29958 | 9 | 3 |
| [AL3PD2_D513](#phase-al-pd-al3pd2-d513); _phase:al-pd:al3pd2-d513_ | Ni2Al3 · D5_13 · hP5 · P-3m1 (164) | tier A: standard phase name | stable in 3 of 3 calculated diagram(s): 300–1224.51 K, x(Pd) 0.3871–0.4124 | 4 | 3 |
| [AL3PD5](#phase-al-pd-al3pd5); _phase:al-pd:al3pd5_ | Ge3Rh5 · oP16 · Pbam (55) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 3 of 3 calculated diagram(s): 880–1592.92 K, x(Pd) 0.625–0.625 | 6 | 3 |
| [AL4PD](#phase-al-pd-al4pd); _phase:al-pd:al4pd_ |  | needs_review | stable in 3 of 3 calculated diagram(s): 300–877.27 K, x(Pd) 0.2–0.2 | 4 | 3 |
| [ALPD_B2](#phase-al-pd-alpd-b2); _phase:al-pd:alpd-b2_ | CsCl · B2 · cP2 · Pm-3m (221) | tier A: standard phase name | stable in 2 of 2 calculated diagram(s): 300–1918.84 K, x(Pd) 0.44239–0.57122 | 8 | 2 |
| [ALPD2_C37](#phase-al-pd-alpd2-c37); _phase:al-pd:alpd2-c37_ | Co2Si · C37 · oP12 · Pnma (62) | tier A: standard phase name | stable in 3 of 3 calculated diagram(s): 300–1691.49 K, x(Pd) 0.6465–0.72644 | 12 | 3 |
| [BCC_A2](#phase-al-pd-bcc-a2); _phase:al-pd:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | not stable in 3 calculated diagram(s) | 0 | 4 |
| [B2_BCC](#phase-al-pd-bcc-b2); _phase:al-pd:bcc-b2_ | CsCl · B2 · cP2 · Pm-3m (221) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–1940.47 K, x(Pd) 0.45766–0.54792 | 0 | 1 |
| [FCC_A1](#phase-al-pd-fcc-a1); _phase:al-pd:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | stable in 3 of 3 calculated diagram(s): 300–2433 K, x(Pd) 0–1 | 8 | 3 |
| [HCP_A3](#phase-al-pd-hcp-a3); _phase:al-pd:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | not stable in 3 calculated diagram(s) | 0 | 3 |
| [LIQUID](#phase-al-pd-liquid); _phase:al-pd:liquid_ | liquid | liquid | stable in 3 of 3 calculated diagram(s): 879.9–2500 K, x(Pd) 0–1 | 21 | 3 |

## AL21PD8 (Al–Pd)

- Id: `phase:al-pd:al21pd8`; status `assigned`
- Structure: Al21Pt8 · tI116 · I4_1/a (88); type `st:al21pt8-ti116`; tier B: DFT-supported (unique MP + OQMD match); confidence high
- Stoichiometry: Al 0.7241, Pd 0.2759
- Stability: stable in 3 of 3 calculated diagram(s): 300–1063.8 K, x(Pd) 0.27586–0.27586
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al21pd8)

Names (7): _corpus: _corpus:phase:al-pd:al21pd8  
_mp: _mp:mp-aaaaacfq  
_oqmd: _oqmd:oqmd-54929  
_paper: _paper:10.1016/j.intermet.2005.04.001:Al21Pd8  
_tdb: _tdb:AlPd-06Li.tdb:AL21PD8, tdb:AlPd-17Dur.tdb:AL21PD8, tdb:AlPd-21Hom.tdb:AL21PD8  


### TDB models of AL21PD8 (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL21PD8, type code %, sha256 `fe0d623a97496170…`

~~~~text
55: PHASE AL21PD8 % 2 21 8 !
56: CONST AL21PD8 : AL : PD : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL21PD8, type code %, sha256 `53154de006cd77b7…`

~~~~text
58: PHASE AL21PD8 % 2 21 8 !
59: CONST AL21PD8 : AL : PD : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL21PD8, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
66: PHASE AL21PD8 % 2 21 8 !
67: CONST AL21PD8 : AL : PD : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## AL2PD5 (Al–Pd)

- Id: `phase:al-pd:al2pd5`; status `assigned`
- Structure: Ga2Pd5 · oP28 · Pnma (62); type `st:ga2pd5-op28`; 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](https://doi.org/10.1016/j.calphad.2025.102833)
- Caveat: not certain from the name or DFT alone (no_structure_token, off_stoichiometric_model); structure as stated in the SGTE crystallographic table for this phase name and system
- Stability: stable in 3 of 3 calculated diagram(s): 300–1246.17 K, x(Pd) 0.70404–0.71429
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al2pd5)

Names (5): _corpus: _corpus:phase:al-pd:al2pd5  
_paper: _paper:10.1016/j.intermet.2005.04.001:(Al2Pd5)  
_tdb: _tdb:AlPd-06Li.tdb:AL2PD5, tdb:AlPd-17Dur.tdb:AL2PD5, tdb:AlPd-21Hom.tdb:AL2PD5  


### TDB models of AL2PD5 (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL2PD5, type code %, sha256 `fe0d623a97496170…`

~~~~text
75: PHASE AL2PD5 % 2 2 5 !
76: CONST AL2PD5 : AL : AL PD% : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL2PD5, type code %, sha256 `53154de006cd77b7…`

~~~~text
78: PHASE AL2PD5 % 2 2 5 !
79: CONST AL2PD5 : AL : AL PD% : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL2PD5, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
81: PHASE AL2PD5 % 2 2 5 !
82: CONST AL2PD5 : AL : AL PD% : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## AL3PD (Al–Pd)

- Id: `phase:al-pd:al3pd`; status `needs_review`
- No structure assigned. Why: no_structure_token; off_stoichiometric_model; sgte_mmc2_row_incomplete
- Candidate (dft_mp): I4_1/a (88) — on-hull MP Al21Pd8 at x(PD)=0.2759
- Candidate (dft_oqmd): I41/a (88) — on-hull OQMD Al21 Pd8 at x(PD)=0.2759
- Candidate (literature_printed): (Al3Pd) · oP\* — printed with a label mapped to this phase
- Candidate (sgte_mmc2): (Al3Pd) · Pna2_1 (33) — Hallstedt 2025 mmc2 row for AL3PD: Al3Pd
- Stability: stable in 3 of 3 calculated diagram(s): 852.09–1059.13 K, x(Pd) 0.25–0.29958
- Literature: 9 values (9 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al3pd)

Names (6): _corpus: _corpus:phase:al-pd:al3pd  
_paper: _paper:10.1016/j.intermet.2005.04.001:Al3Pd, paper:10.3390/met11111803:Al3Pd  
_tdb: _tdb:AlPd-06Li.tdb:AL3PD, tdb:AlPd-17Dur.tdb:AL3PD, tdb:AlPd-21Hom.tdb:AL3PD  


### TDB models of AL3PD (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL3PD, type code %, sha256 `fe0d623a97496170…`

~~~~text
50: PHASE AL3PD % 2 3 1 !
51: CONST AL3PD : AL : PD : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL3PD, type code %, sha256 `53154de006cd77b7…`

~~~~text
53: PHASE AL3PD % 2 3 1 !
54: CONST AL3PD : AL% PD : AL PD% : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL3PD, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
61: PHASE AL3PD % 2 3 1 !
62: CONST AL3PD : AL : PD : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_

## AL3PD2_D513 (Al–Pd)

- Id: `phase:al-pd:al3pd2-d513`; status `assigned`
- Structure: Ni2Al3 · D5_13 · hP5 · P-3m1 (164); type `st:d5-13-ni2al3-hp5`; tier A: standard phase name; confidence high
- Caveat: partitioned order/disorder model in AlPd-06Li.tdb also describes the disordered state
- Caveat: partitioned order/disorder model in AlPd-17Dur.tdb also describes the disordered state
- Caveat: partitioned order/disorder model in AlPd-21Hom.tdb also describes the disordered state
- Stability: stable in 3 of 3 calculated diagram(s): 300–1224.51 K, x(Pd) 0.3871–0.4124
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al3pd2-d513)

Names (5): _corpus: _corpus:phase:al-pd:al3pd2-d513  
_paper: _paper:10.1016/j.intermet.2005.04.001:(Al3Pd2)  
_tdb: _tdb:AlPd-06Li.tdb:AL3PD2_D513, tdb:AlPd-17Dur.tdb:AL3PD2_D513, tdb:AlPd-21Hom.tdb:AL3PD2_D513  


### TDB models of AL3PD2_D513 (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL3PD2_D513, type code %, sha256 `fe0d623a97496170…`

~~~~text
60: PHASE AL3PD2_D513 % 2 3 2 !
61: CONST AL3PD2_D513 : AL% PD : AL PD% : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL3PD2_D513, type code %, sha256 `53154de006cd77b7…`

~~~~text
63: PHASE AL3PD2_D513 % 2 3 2 !
64: CONST AL3PD2_D513 : AL% PD : AL PD% : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL3PD2_D513, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
71: PHASE AL3PD2_D513 % 2 3 2 !
72: CONST AL3PD2_D513 : AL% PD : AL PD% : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## AL3PD5 (Al–Pd)

- Id: `phase:al-pd:al3pd5`; status `assigned`
- Structure: Ge3Rh5 · oP16 · Pbam (55); type `st:ge3rh5-op16`; 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](https://doi.org/10.1016/j.calphad.2025.102833)
- Caveat: not certain from the name or DFT alone (no_on_hull_entry_in_mp, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
- Stoichiometry: Al 0.3750, Pd 0.6250
- Stability: stable in 3 of 3 calculated diagram(s): 880–1592.92 K, x(Pd) 0.625–0.625
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al3pd5)

Names (5): _corpus: _corpus:phase:al-pd:al3pd5  
_paper: _paper:10.1016/j.intermet.2005.04.001:Al3Pd5  
_tdb: _tdb:AlPd-06Li.tdb:AL3PD5, tdb:AlPd-17Dur.tdb:AL3PD5, tdb:AlPd-21Hom.tdb:AL3PD5  


### TDB models of AL3PD5 (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL3PD5, type code %, sha256 `fe0d623a97496170…`

~~~~text
70: PHASE AL3PD5 % 2 3 5 !
71: CONST AL3PD5 : AL : PD : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL3PD5, type code %, sha256 `53154de006cd77b7…`

~~~~text
73: PHASE AL3PD5 % 2 3 5 !
74: CONST AL3PD5 : AL : PD : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL3PD5, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
76: PHASE AL3PD5 % 2 3 5 !
77: CONST AL3PD5 : AL : PD : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## AL4PD (Al–Pd)

- Id: `phase:al-pd:al4pd`; status `needs_review`
- No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
- Candidate (literature_printed): (Al4Pd) · hP\* — printed with a label mapped to this phase
- Candidate (sgte_mmc2): (Al4Pd) · P6_322 (182) — Hallstedt 2025 mmc2 row for AL4PD: Al4Pd
- Stoichiometry: Al 0.8000, Pd 0.2000
- Stability: stable in 3 of 3 calculated diagram(s): 300–877.27 K, x(Pd) 0.2–0.2
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:al4pd)

Names (5): _corpus: _corpus:phase:al-pd:al4pd  
_paper: _paper:10.1016/j.intermet.2005.04.001:Al4Pd  
_tdb: _tdb:AlPd-06Li.tdb:AL4PD, tdb:AlPd-17Dur.tdb:AL4PD, tdb:AlPd-21Hom.tdb:AL4PD  


### TDB models of AL4PD (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): AL4PD, type code %, sha256 `fe0d623a97496170…`

~~~~text
45: PHASE AL4PD % 2 4 1 !
46: CONST AL4PD : AL : PD : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): AL4PD, type code %, sha256 `53154de006cd77b7…`

~~~~text
48: PHASE AL4PD % 2 4 1 !
49: CONST AL4PD : AL : PD : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): AL4PD, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
56: PHASE AL4PD % 2 4 1 !
57: CONST AL4PD : AL : PD : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_

## ALPD_B2 (Al–Pd)

- Id: `phase:al-pd:alpd-b2`; status `assigned`
- Structure: CsCl · B2 · cP2 · Pm-3m (221); type `st:b2-cscl-cp2`; tier A: standard phase name; confidence high
- Stability: stable in 2 of 2 calculated diagram(s): 300–1918.84 K, x(Pd) 0.44239–0.57122
- Literature: 8 values (8 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:alpd-b2)

Names (4): _corpus: _corpus:phase:al-pd:alpd-b2  
_paper: _paper:10.1016/j.intermet.2005.04.001:(AlPd)  
_tdb: _tdb:AlPd-06Li.tdb:ALPD_B2, tdb:AlPd-17Dur.tdb:ALPD_B2  


### TDB models of ALPD_B2 (2): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): ALPD_B2, type code %, sha256 `fe0d623a97496170…`

~~~~text
65: PHASE ALPD_B2 % 2 1 1 !
66: CONST ALPD_B2 : AL% PD : PD% VA : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): ALPD_B2, type code %, sha256 `53154de006cd77b7…`

~~~~text
68: PHASE ALPD_B2 % 2 1 1 !
69: CONST ALPD_B2 : AL% PD : PD% VA : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## ALPD2_C37 (Al–Pd)

- Id: `phase:al-pd:alpd2-c37`; status `assigned`
- Structure: Co2Si · C37 · oP12 · Pnma (62); type `st:c37-co2si-op12`; tier A: standard phase name; confidence high
- Caveat: partitioned order/disorder model in AlPd-06Li.tdb also describes the disordered state
- Caveat: partitioned order/disorder model in AlPd-17Dur.tdb also describes the disordered state
- Caveat: partitioned order/disorder model in AlPd-21Hom.tdb also describes the disordered state
- Stability: stable in 3 of 3 calculated diagram(s): 300–1691.49 K, x(Pd) 0.6465–0.72644
- Literature: 12 values (12 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:alpd2-c37)

Names (5): _corpus: _corpus:phase:al-pd:alpd2-c37  
_paper: _paper:10.1016/j.intermet.2005.04.001:(AlPd2)  
_tdb: _tdb:AlPd-06Li.tdb:ALPD2_C37, tdb:AlPd-17Dur.tdb:ALPD2_C37, tdb:AlPd-21Hom.tdb:ALPD2_C37  


### TDB models of ALPD2_C37 (3): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): ALPD2_C37, type code %, sha256 `fe0d623a97496170…`

~~~~text
80: PHASE ALPD2_C37 % 2 1 2 !
81: CONST ALPD2_C37 : AL% PD : AL PD% : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): ALPD2_C37, type code %, sha256 `53154de006cd77b7…`

~~~~text
83: PHASE ALPD2_C37 % 2 1 2 !
84: CONST ALPD2_C37 : AL% PD : AL PD% : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): ALPD2_C37, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
86: PHASE ALPD2_C37 % 2 1 2 !
87: CONST ALPD2_C37 : AL% PD : AL PD% : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## BCC_A2 (Al–Pd)

- Id: `phase:al-pd: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 3 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:bcc-a2)

Names (5): _corpus: _corpus:phase:al-pd:bcc-a2  
_tdb: _tdb:AlPd-06Li.tdb:BCC_A2, tdb:AlPd-17Dur.tdb:BCC_A2, tdb:AlPd-21Hom.tdb:A2_BCC, tdb:AlPd-21Hom.tdb:BCC_A2  


### TDB models of BCC_A2 (4): PHASE and CONSTITUENT statements as written

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): BCC_A2, type code %B, sha256 `fe0d623a97496170…`

~~~~text
35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : AL PD : VA : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): BCC_A2, type code %B, sha256 `53154de006cd77b7…`

~~~~text
38: PHASE BCC_A2 %B 2 1 3 !
39: CONST BCC_A2 : AL PD : VA : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): A2_BCC, type code %B, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
41: PHASE A2_BCC %B 2 1 3 !
42: CONST A2_BCC : AL PD VA : VA : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): BCC_A2, type code %B, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : AL PD : VA : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_

## B2_BCC (Al–Pd)

- Id: `phase:al-pd:bcc-b2`; status `assigned`
- Structure: CsCl · B2 · cP2 · Pm-3m (221); type `st:b2-cscl-cp2`; tier A: standard phase name; confidence high
- Caveat: AlPd-21Hom.tdb: ordered phase with disordered part A2_BCC (order/disorder model)
- Caveat: partitioned order/disorder model in AlPd-21Hom.tdb also describes the disordered state
- Stability: stable in 1 of 1 calculated diagram(s): 300–1940.47 K, x(Pd) 0.45766–0.54792
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:bcc-b2)

Names (2): _corpus: _corpus:phase:al-pd:bcc-b2  
_tdb: _tdb:AlPd-21Hom.tdb:B2_BCC  


### TDB models of B2_BCC (1): PHASE and CONSTITUENT statements as written

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): B2_BCC, type code %BO, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
46: PHASE B2_BCC %BO 3 0.5 0.5 3 !
47: CONST B2_BCC : AL% PD VA : AL PD% VA : VA : !
~~~~

Example references (1 of 1; assessments first): 

- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_

## FCC_A1 (Al–Pd)

- Id: `phase:al-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 3 of 3 calculated diagram(s): 300–2433 K, x(Pd) 0–1
- Literature: 8 values (8 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:fcc-a1)

Names (6): _corpus: _corpus:phase:al-pd:fcc-a1  
_paper: _paper:10.1016/j.intermet.2005.04.001:(Al), paper:10.1016/j.intermet.2005.04.001:(Pd)  
_tdb: _tdb:AlPd-06Li.tdb:FCC_A1, tdb:AlPd-17Dur.tdb:FCC_A1, tdb:AlPd-21Hom.tdb:FCC_A1  


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

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): FCC_A1, type code %A, sha256 `fe0d623a97496170…`

~~~~text
30: PHASE FCC_A1 %A 2 1 1 !
31: CONST FCC_A1 : AL PD : VA : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): FCC_A1, type code %A, sha256 `53154de006cd77b7…`

~~~~text
33: PHASE FCC_A1 %A 2 1 1 !
34: CONST FCC_A1 : AL PD : VA : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): FCC_A1, type code %A, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : AL PD : VA : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_cited as the source of values for this phase_

## HCP_A3 (Al–Pd)

- Id: `phase:al-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
- Stability: not stable in 3 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:hcp-a3)

Names (4): _corpus: _corpus:phase:al-pd:hcp-a3  
_tdb: _tdb:AlPd-06Li.tdb:HCP_A3, tdb:AlPd-17Dur.tdb:HCP_A3, tdb:AlPd-21Hom.tdb:HCP_A3  


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

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): HCP_A3, type code %A, sha256 `fe0d623a97496170…`

~~~~text
40: PHASE HCP_A3 %A 2 1 0.5 !
41: CONST HCP_A3 : AL PD : VA : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): HCP_A3, type code %A, sha256 `53154de006cd77b7…`

~~~~text
43: PHASE HCP_A3 %A 2 1 0.5 !
44: CONST HCP_A3 : AL PD : VA : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): HCP_A3, type code %A, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
51: PHASE HCP_A3 %A 2 1 0.5 !
52: CONST HCP_A3 : AL PD : VA : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase_

## LIQUID (Al–Pd)

- Id: `phase:al-pd:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 3 of 3 calculated diagram(s): 879.9–2500 K, x(Pd) 0–1
- Literature: 21 values (21 accepted) from 2 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:al-pd:liquid)

Names (6): _corpus: _corpus:phase:al-pd:liquid  
_paper: _paper:10.1016/j.intermet.2005.04.001:L, paper:10.3390/met11111803:liquid  
_tdb: _tdb:AlPd-06Li.tdb:LIQUID, tdb:AlPd-17Dur.tdb:LIQUID, tdb:AlPd-21Hom.tdb:LIQUID  


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

[AlPd-06Li.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-06Li.tdb): LIQUID, type code %, sha256 `fe0d623a97496170…`

~~~~text
25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : AL PD : !
~~~~

[AlPd-17Dur.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-17Dur.tdb): LIQUID, type code %, sha256 `53154de006cd77b7…`

~~~~text
28: PHASE LIQUID:L % 1 1 !
29: CONST LIQUID:L : AL PD : !
~~~~

[AlPd-21Hom.tdb](https://orchid-project.org/data/databases/sgte-binary/AlPd-21Hom.tdb): LIQUID, type code %, sha256 `16c4c1ecb5dbb2e6…`

~~~~text
26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : AL PD : !
~~~~

Example references (4 of 4; assessments first): 

- [doi:10.1016/j.intermet.2005.04.001](https://doi.org/10.1016/j.intermet.2005.04.001) Mei Li, Changrong Li, Fuming Wang, Weijing Zhang, Thermodynamic assessment of the Al–Pd system, Intermetallics 14, 39-46 (2006).  
_assessment that models this phase; reports values for this phase_
- [doi:10.3390/met11111803](https://doi.org/10.3390/met11111803) Viera Homolová, Aleš Kroupa, Thermodynamic Modeling of the Al–Co–Pd Ternary System, Aluminum Rich Corner, Metals 11, 1803 (2021).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1088/1742-6596/809/1/012008](https://doi.org/10.1088/1742-6596/809/1/012008) Libor Ďuriška, Ivona Černičková, Roman Čička, Jozef Janovec, Contribution to thermodynamic description of Al-Pd system, J. Phys.: Conf. Ser. 809, 012008 (2017).  
_assessment that models this phase_
- [doi:10.1007/bf02873025](https://doi.org/10.1007/bf02873025) McAlister AJ. The Al–Pd system. Bull Alloy Phase Diagram 1986;7: 368–74.  
_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). 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).