# Er–Pd phases

> Er–Pd system: 14 phases (tier A 7, tier B 1, tier C 1, liquid 1, needs_review 4); 13 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/ER-PD.html · Markdown: https://data.orchid-project.org/phases/pages/ER-PD.md

14 phases (tier A 7, tier B 1, tier C 1, liquid 1, needs_review 4); 13 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=ER-PD) · [full JSON](https://data.orchid-project.org/phases/systems/ER-PD.json) · [Er–Pd system page](https://data.orchid-project.org/systems/ER-PD.html) · [Markdown](https://data.orchid-project.org/phases/pages/ER-PD.md) · [field reference](https://data.orchid-project.org/phases/SCHEMA.md)

Table: Phases of the Er–Pd system (14)

| Phase | Structure | Basis | Stability (calculated) | Literature values | TDB models |
|---|---|---|---|---:|---:|
| [BCC_A2](#phase-er-pd-bcc-a2); _phase:er-pd:bcc-a2_ | W · A2 · cI2 · Im-3m (229) | tier A: standard phase name | not stable in 1 calculated diagram(s) | 0 | 1 |
| [ER10PD21](#phase-er-pd-er10pd21); _phase:er-pd:er10pd21_ |  | needs_review | stable in 1 of 1 calculated diagram(s): 300–1607.77 K, x(Pd) 0.67742–0.67742 | 4 | 1 |
| [ER2PD3_HT](#phase-er-pd-er2pd3-ht); _phase:er-pd:er2pd3-ht_ |  | needs_review | stable in 1 of 1 calculated diagram(s): 1423.12–1595.68 K, x(Pd) 0.6–0.6 | 6 | 1 |
| [ER2PD3_LT](#phase-er-pd-er2pd3-lt); _phase:er-pd:er2pd3-lt_ |  | needs_review | stable in 1 of 1 calculated diagram(s): 300–1423.12 K, x(Pd) 0.6–0.6 | 2 | 1 |
| [ER3PD2_D5A](#phase-er-pd-er3pd2-d5a); _phase:er-pd:er3pd2-d5a_ | Si2U3 · D5_a · tP10 · P4/mbm (127) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–1264.91 K, x(Pd) 0.4–0.4 | 6 | 1 |
| [ER3PD4](#phase-er-pd-er3pd4); _phase:er-pd:er3pd4_ | Pd4Pu3 · hR14 · R-3 (148) | tier B: DFT-supported (unique MP + OQMD match) | stable in 1 of 1 calculated diagram(s): 300–1721.93 K, x(Pd) 0.57143–0.57143 | 8 | 1 |
| [ER5PD2](#phase-er-pd-er5pd2); _phase:er-pd:er5pd2_ | Dy5Pd2 · cF144 · Fd-3m (227) | tier C: assessor-stated (Hallstedt 2025 crystallographic table) | stable in 1 of 1 calculated diagram(s): 300–1211.99 K, x(Pd) 0.28571–0.28571 | 6 | 1 |
| [ERPD_B2](#phase-er-pd-erpd-b2); _phase:er-pd:erpd-b2_ | CsCl · B2 · cP2 · Pm-3m (221) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 821.12–1812.46 K, x(Pd) 0.47745–0.5 | 10 | 1 |
| [ERPD_B27](#phase-er-pd-erpd-b27); _phase:er-pd:erpd-b27_ | FeB · B27 · oP8 · Pnma (62) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–838.14 K, x(Pd) 0.49417–0.5 | 4 | 1 |
| [ERPD3_L12](#phase-er-pd-erpd3-l12); _phase:er-pd:erpd3-l12_ | AuCu3 · L1_2 · cP4 · Pm-3m (221) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–1982.65 K, x(Pd) 0.75–0.78815 | 10 | 1 |
| [ERPD7](#phase-er-pd-erpd7); _phase:er-pd:erpd7_ |  | needs_review | stable in 1 of 1 calculated diagram(s): 300–723.01 K, x(Pd) 0.875–0.875 | 4 | 1 |
| [FCC_A1](#phase-er-pd-fcc-a1); _phase:er-pd:fcc-a1_ | Cu · A1 · cF4 · Fm-3m (225) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–1828 K, x(Pd) 0.88152–1 | 6 | 1 |
| [HCP_A3](#phase-er-pd-hcp-a3); _phase:er-pd:hcp-a3_ | Mg · A3 · hP2 · P6_3/mmc (194) | tier A: standard phase name | stable in 1 of 1 calculated diagram(s): 300–1817 K, x(Pd) 0–0 | 2 | 1 |
| [LIQUID](#phase-er-pd-liquid); _phase:er-pd:liquid_ | liquid | liquid | stable in 1 of 1 calculated diagram(s): 1189.65–2500 K, x(Pd) 0–1 | 24 | 1 |

## BCC_A2 (Er–Pd)

- Id: `phase:er-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 1 calculated diagram(s)
- Literature: 0 values (0 accepted) from 0 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:bcc-a2)

Names (2): _corpus: _corpus:phase:er-pd:bcc-a2  
_tdb: _tdb:ErPd-00Du.tdb:BCC_A2  


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

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): BCC_A2, type code %B, sha256 `cc635afc1ea75b34…`

~~~~text
33: PHASE BCC_A2 %B 2 1 3 !
34: CONST BCC_A2 : ER PD : VA : !
~~~~

Example references (1 of 1; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase_

## ER10PD21 (Er–Pd)

- Id: `phase:er-pd:er10pd21`; status `needs_review`
- No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
- Candidate (literature_printed): (Er10Pd21) · ? — printed with a label mapped to this phase
- Candidate (sgte_mmc2): (Er10Pd21) — Hallstedt 2025 mmc2 row for ER10PD21: Er10Pd21
- Stoichiometry: Er 0.3226, Pd 0.6774
- Stability: stable in 1 of 1 calculated diagram(s): 300–1607.77 K, x(Pd) 0.67742–0.67742
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er10pd21)

Names (3): _corpus: _corpus:phase:er-pd:er10pd21  
_paper: _paper:10.1016/s0925-8388(99)00691-x:Er10Pd21  
_tdb: _tdb:ErPd-00Du.tdb:ER10PD21  


### TDB models of ER10PD21 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER10PD21, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
78: PHASE ER10PD21 % 2 10 21 !
79: CONST ER10PD21 : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ER2PD3_HT (Er–Pd)

- Id: `phase:er-pd:er2pd3-ht`; status `needs_review`
- No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
- Candidate (sgte_mmc2): (Er2Pd3_HT) — Hallstedt 2025 mmc2 row for ER2PD3_HT: Er2Pd3-HT
- Stoichiometry: Er 0.4000, Pd 0.6000
- Stability: stable in 1 of 1 calculated diagram(s): 1423.12–1595.68 K, x(Pd) 0.6–0.6
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er2pd3-ht)

Names (3): _corpus: _corpus:phase:er-pd:er2pd3-ht  
_paper: _paper:10.1016/s0925-8388(99)00691-x:βEr2Pd3  
_tdb: _tdb:ErPd-00Du.tdb:ER2PD3_HT  


### TDB models of ER2PD3_HT (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER2PD3_HT, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
73: PHASE ER2PD3_HT % 2 2 3 !
74: CONST ER2PD3_HT : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ER2PD3_LT (Er–Pd)

- Id: `phase:er-pd:er2pd3-lt`; status `needs_review`
- No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
- Candidate (sgte_mmc2): (Er2Pd3_LT) — Hallstedt 2025 mmc2 row for ER2PD3_LT: Er2Pd3-LT
- Stoichiometry: Er 0.4000, Pd 0.6000
- Stability: stable in 1 of 1 calculated diagram(s): 300–1423.12 K, x(Pd) 0.6–0.6
- Literature: 2 values (2 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er2pd3-lt)

Names (3): _corpus: _corpus:phase:er-pd:er2pd3-lt  
_paper: _paper:10.1016/s0925-8388(99)00691-x:αEr2Pd3  
_tdb: _tdb:ErPd-00Du.tdb:ER2PD3_LT  


### TDB models of ER2PD3_LT (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER2PD3_LT, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
68: PHASE ER2PD3_LT % 2 2 3 !
69: CONST ER2PD3_LT : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ER3PD2_D5A (Er–Pd)

- Id: `phase:er-pd:er3pd2-d5a`; status `assigned`
- Structure: Si2U3 · D5_a · tP10 · P4/mbm (127); type `st:d5-a-si2u3-tp10`; tier A: standard phase name; confidence high
- Stoichiometry: Er 0.6000, Pd 0.4000
- Stability: stable in 1 of 1 calculated diagram(s): 300–1264.91 K, x(Pd) 0.4–0.4
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er3pd2-d5a)

Names (3): _corpus: _corpus:phase:er-pd:er3pd2-d5a  
_paper: _paper:10.1016/s0925-8388(99)00691-x:Er3Pd2  
_tdb: _tdb:ErPd-00Du.tdb:ER3PD2_D5A  


### TDB models of ER3PD2_D5A (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER3PD2_D5A, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
48: PHASE ER3PD2_D5A % 2 3 2 !
49: CONST ER3PD2_D5A : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ER3PD4 (Er–Pd)

- Id: `phase:er-pd:er3pd4`; status `assigned`
- Structure: Pd4Pu3 · hR14 · R-3 (148); type `st:pd4pu3-hr14`; tier B: DFT-supported (unique MP + OQMD match); confidence high
- Stoichiometry: Er 0.4286, Pd 0.5714
- Stability: stable in 1 of 1 calculated diagram(s): 300–1721.93 K, x(Pd) 0.57143–0.57143
- Literature: 8 values (8 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er3pd4)

Names (5): _corpus: _corpus:phase:er-pd:er3pd4  
_mp: _mp:mp-aaackwhi  
_oqmd: _oqmd:oqmd-30026  
_paper: _paper:10.1016/s0925-8388(99)00691-x:Er3Pd4  
_tdb: _tdb:ErPd-00Du.tdb:ER3PD4  


### TDB models of ER3PD4 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER3PD4, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
63: PHASE ER3PD4 % 2 3 4 !
64: CONST ER3PD4 : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ER5PD2 (Er–Pd)

- Id: `phase:er-pd:er5pd2`; status `assigned`
- Structure: Dy5Pd2 · cF144 · Fd-3m (227); type `st:dy5pd2-cf144`; 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_both, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
- Stoichiometry: Er 0.7143, Pd 0.2857
- Stability: stable in 1 of 1 calculated diagram(s): 300–1211.99 K, x(Pd) 0.28571–0.28571
- Literature: 6 values (6 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:er5pd2)

Names (3): _corpus: _corpus:phase:er-pd:er5pd2  
_paper: _paper:10.1016/s0925-8388(99)00691-x:Er5Pd2  
_tdb: _tdb:ErPd-00Du.tdb:ER5PD2  


### TDB models of ER5PD2 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ER5PD2, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
43: PHASE ER5PD2 % 2 5 2 !
44: CONST ER5PD2 : ER : PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ERPD_B2 (Er–Pd)

- Id: `phase:er-pd:erpd-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 1 of 1 calculated diagram(s): 821.12–1812.46 K, x(Pd) 0.47745–0.5
- Literature: 10 values (10 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:erpd-b2)

Names (3): _corpus: _corpus:phase:er-pd:erpd-b2  
_paper: _paper:10.1016/s0925-8388(99)00691-x:βErPd  
_tdb: _tdb:ErPd-00Du.tdb:ERPD_B2  


### TDB models of ERPD_B2 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ERPD_B2, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
58: PHASE ERPD_B2 % 2 1 1 !
59: CONST ERPD_B2 : ER : ER PD% : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ERPD_B27 (Er–Pd)

- Id: `phase:er-pd:erpd-b27`; status `assigned`
- Structure: FeB · B27 · oP8 · Pnma (62); type `st:b27-feb-op8`; tier A: standard phase name; confidence high
- Stability: stable in 1 of 1 calculated diagram(s): 300–838.14 K, x(Pd) 0.49417–0.5
- Literature: 4 values (4 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:erpd-b27)

Names (3): _corpus: _corpus:phase:er-pd:erpd-b27  
_paper: _paper:10.1016/s0925-8388(99)00691-x:αErPd  
_tdb: _tdb:ErPd-00Du.tdb:ERPD_B27  


### TDB models of ERPD_B27 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ERPD_B27, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
53: PHASE ERPD_B27 % 2 1 1 !
54: CONST ERPD_B27 : ER : ER PD% : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## ERPD3_L12 (Er–Pd)

- Id: `phase:er-pd:erpd3-l12`; status `assigned`
- Structure: AuCu3 · L1_2 · cP4 · Pm-3m (221); type `st:l1-2-aucu3-cp4`; tier A: standard phase name; confidence high
- Stability: stable in 1 of 1 calculated diagram(s): 300–1982.65 K, x(Pd) 0.75–0.78815
- Literature: 10 values (7 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:erpd3-l12)

Names (3): _corpus: _corpus:phase:er-pd:erpd3-l12  
_paper: _paper:10.1016/s0925-8388(99)00691-x:ErPd3  
_tdb: _tdb:ErPd-00Du.tdb:ERPD3_L12  


### TDB models of ERPD3_L12 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ERPD3_L12, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
83: PHASE ERPD3_L12 % 2 1 3 !
84: CONST ERPD3_L12 : ER% PD : PD : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_
- [doi:10.1007/bf00719703](https://doi.org/10.1007/bf00719703) Y. Sakamoto, K. Takao, Y. Nagaoka, The palladium-rich Pd-Ho(Er) systems, J Mater Sci Lett 10, 341-344 (1991).  
_cited as the source of values for this phase_

## ERPD7 (Er–Pd)

- Id: `phase:er-pd:erpd7`; status `needs_review`
- No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
- Candidate (literature_printed): (ErPd7) · ? — printed with a label mapped to this phase
- Candidate (sgte_mmc2): (ErPd7) — Hallstedt 2025 mmc2 row for ERPD7: ErPd7
- Stoichiometry: Er 0.1250, Pd 0.8750
- Stability: stable in 1 of 1 calculated diagram(s): 300–723.01 K, x(Pd) 0.875–0.875
- Literature: 4 values (1 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:erpd7)

Names (4): _corpus: _corpus:phase:er-pd:erpd7  
_paper: _paper:10.1016/s0925-8388(99)00691-x:ErPd7, paper:10.1016/s0925-8388(99)00691-x:ErPd7^c  
_tdb: _tdb:ErPd-00Du.tdb:ERPD7  


### TDB models of ERPD7 (1): PHASE and CONSTITUENT statements as written

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): ERPD7, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
88: PHASE ERPD7 % 2 1 7 !
89: CONST ERPD7 : ER : PD : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_
- [doi:10.1007/bf00719703](https://doi.org/10.1007/bf00719703) Y. Sakamoto, K. Takao, Y. Nagaoka, The palladium-rich Pd-Ho(Er) systems, J Mater Sci Lett 10, 341-344 (1991).  
_cited as the source of values for this phase_

## FCC_A1 (Er–Pd)

- Id: `phase:er-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): 300–1828 K, x(Pd) 0.88152–1
- Literature: 6 values (3 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:fcc-a1)

Names (3): _corpus: _corpus:phase:er-pd:fcc-a1  
_paper: _paper:10.1016/s0925-8388(99)00691-x:f.c.c.(Pd)  
_tdb: _tdb:ErPd-00Du.tdb:FCC_A1  


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

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): FCC_A1, type code %A, sha256 `cc635afc1ea75b34…`

~~~~text
28: PHASE FCC_A1 %A 2 1 1 !
29: CONST FCC_A1 : ER PD% : VA : !
~~~~

Example references (3 of 3; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_
- [doi:10.1007/bf00719703](https://doi.org/10.1007/bf00719703) Y. Sakamoto, K. Takao, Y. Nagaoka, The palladium-rich Pd-Ho(Er) systems, J Mater Sci Lett 10, 341-344 (1991).  
_cited as the source of values for this phase_

## HCP_A3 (Er–Pd)

- Id: `phase:er-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: stable in 1 of 1 calculated diagram(s): 300–1817 K, x(Pd) 0–0
- Literature: 2 values (2 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:hcp-a3)

Names (3): _corpus: _corpus:phase:er-pd:hcp-a3  
_paper: _paper:10.1016/s0925-8388(99)00691-x:h.c.p.(Er)  
_tdb: _tdb:ErPd-00Du.tdb:HCP_A3  


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

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): HCP_A3, type code %A, sha256 `cc635afc1ea75b34…`

~~~~text
38: PHASE HCP_A3 %A 2 1 0.5 !
39: CONST HCP_A3 : ER% PD : VA : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_cited as the source of values for this phase_

## LIQUID (Er–Pd)

- Id: `phase:er-pd:liquid`; status `assigned`
- Structure: liquid; type `st:liquid`; liquid; confidence high
- Stability: stable in 1 of 1 calculated diagram(s): 1189.65–2500 K, x(Pd) 0–1
- Literature: 24 values (24 accepted) from 1 papers
- Interactive: [phase registry entry](https://orchid-project.org/phases/#phase:er-pd:liquid)

Names (3): _corpus: _corpus:phase:er-pd:liquid  
_paper: _paper:10.1016/s0925-8388(99)00691-x:Liq.  
_tdb: _tdb:ErPd-00Du.tdb:LIQUID  


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

[ErPd-00Du.tdb](https://orchid-project.org/data/databases/sgte-binary/ErPd-00Du.tdb): LIQUID, type code %, sha256 `cc635afc1ea75b34…`

~~~~text
23: PHASE LIQUID:L % 1 1 !
24: CONST LIQUID:L : ER PD : !
~~~~

Example references (2 of 2; assessments first): 

- [doi:10.1016/S0925-8388(99)00691-X](https://doi.org/10.1016/S0925-8388%2899%2900691-X) Z. Du, H. Yang, J. Alloys Compd., 299, 199-204(2000).  
_assessment that models this phase; reports values for this phase_
- [doi:10.1016/0022-5088(73)90006-4](https://doi.org/10.1016/0022-5088%2873%2990006-4) O Loebich, E Raub, Die Legierungen des Palladiums mit Yttrium, Samarium, Gadolinium, Dysprosium, Holmium und Erbium, Journal of the Less Common Metals 30, 47-62 (1973).  
_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).