Ho–Pd phases

14 phases (tier A 7, tier B 1, tier C 1, liquid 1, needs_review 4); 14 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 · Ho–Pd system page · Markdown · field reference

Phases of the Ho–Pd system (14)
Phase	Structure	Basis	Stability (calculated)	TDB models
BCC_A2 phase:ho-pd:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 1710–1740 K	1
FCC_A1 phase:ho-pd:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2233 K, x(Pd) 0.88155–1	1
HCP_A3 phase:ho-pd:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1700 K	1
HO10PD21 phase:ho-pd:ho10pd21		needs_review	stable in 1 of 1 calculated diagram(s): 300–1580 K	1
HO2PD3_HT phase:ho-pd:ho2pd3-ht		needs_review	stable in 1 of 1 calculated diagram(s): 1400–1550 K, x(Pd) 0.6–0.6	1
HO2PD3_LT phase:ho-pd:ho2pd3-lt		needs_review	stable in 1 of 1 calculated diagram(s): 300–1390 K, x(Pd) 0.6–0.6	1
HO3PD2_D5A phase:ho-pd:ho3pd2-d5a	Si2U3 · D5_a · tP10 · P4/mbm (127)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1240 K, x(Pd) 0.4–0.4	1
HO3PD4 phase:ho-pd:ho3pd4	Pd4Pu3 · hR14 · R-3 (148)	tier B: DFT-supported (unique MP + OQMD match)	stable in 1 of 1 calculated diagram(s): 300–1700 K	1
HO5PD2 phase:ho-pd:ho5pd2	Dy5Pd2 · cF144 · Fd-3m (227)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–1220 K	1
HOPD_B2 phase:ho-pd:hopd-b2	CsCl · B2 · cP2 · Pm-3m (221)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 940–1750 K, x(Pd) 0.49–0.49	1
HOPD_B27 phase:ho-pd:hopd-b27	FeB · B27 · oP8 · Pnma (62)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–970 K, x(Pd) 0.5–0.5	1
HOPD3_L12 phase:ho-pd:hopd3-l12	AuCu3 · L1_2 · cP4 · Pm-3m (221)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2001.54 K, x(Pd) 0.75–0.79332	1
HOPD7 phase:ho-pd:hopd7		needs_review	stable in 1 of 1 calculated diagram(s): 300–748.03 K, x(Pd) 0.875–0.875	1
LIQUID phase:ho-pd:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1180–2500 K, x(Pd) 0–1	1

BCC_A2 (Ho–Pd)

Id: phase:ho-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: stable in 1 of 1 calculated diagram(s): 1710–1740 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:bcc-a2
tdb: tdb:HoPd-00Du.tdb:BCC_A2

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

HoPd-00Du.tdb: BCC_A2, type code %B, sha256 52adcba39cc7336f…

40: PHASE BCC_A2 %B 2 1 3 !
41: CONST BCC_A2 : HO PD : VA : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

FCC_A1 (Ho–Pd)

Id: phase:ho-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): 300–2233 K, x(Pd) 0.88155–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:fcc-a1
tdb: tdb:HoPd-00Du.tdb:FCC_A1

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

HoPd-00Du.tdb: FCC_A1, type code %A, sha256 52adcba39cc7336f…

35: PHASE FCC_A1 %A 2 1 1 !
36: CONST FCC_A1 : HO PD% : VA : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HCP_A3 (Ho–Pd)

Id: phase:ho-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): 300–1700 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:hcp-a3
tdb: tdb:HoPd-00Du.tdb:HCP_A3

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

HoPd-00Du.tdb: HCP_A3, type code %A, sha256 52adcba39cc7336f…

45: PHASE HCP_A3 %A 2 1 0.5 !
46: CONST HCP_A3 : HO% PD : VA : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO10PD21 (Ho–Pd)

Id: phase:ho-pd:ho10pd21; status needs_review
No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
Candidate (sgte_mmc2): (Ho10Pd21) — Hallstedt 2025 mmc2 row for HO10PD21: Ho10Pd21
Stoichiometry: Ho 0.3226, Pd 0.6774
Stability: stable in 1 of 1 calculated diagram(s): 300–1580 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:ho10pd21
tdb: tdb:HoPd-00Du.tdb:HO10PD21

TDB models of HO10PD21 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO10PD21, type code %, sha256 52adcba39cc7336f…

85: PHASE HO10PD21 % 2 10 21 !
86: CONST HO10PD21 : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO2PD3_HT (Ho–Pd)

Id: phase:ho-pd:ho2pd3-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): (Ho2Pd3-HT) — Hallstedt 2025 mmc2 row for HO2PD3_HT: Ho2Pd3-HT
Stoichiometry: Ho 0.4000, Pd 0.6000
Stability: stable in 1 of 1 calculated diagram(s): 1400–1550 K, x(Pd) 0.6–0.6
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:ho2pd3-ht
tdb: tdb:HoPd-00Du.tdb:HO2PD3_HT

TDB models of HO2PD3_HT (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO2PD3_HT, type code %, sha256 52adcba39cc7336f…

80: PHASE HO2PD3_HT % 2 2 3 !
81: CONST HO2PD3_HT : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO2PD3_LT (Ho–Pd)

Id: phase:ho-pd:ho2pd3-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): (Ho2Pd3-LT) — Hallstedt 2025 mmc2 row for HO2PD3_LT: Ho2Pd3-LT
Stoichiometry: Ho 0.4000, Pd 0.6000
Stability: stable in 1 of 1 calculated diagram(s): 300–1390 K, x(Pd) 0.6–0.6
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:ho2pd3-lt
tdb: tdb:HoPd-00Du.tdb:HO2PD3_LT

TDB models of HO2PD3_LT (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO2PD3_LT, type code %, sha256 52adcba39cc7336f…

75: PHASE HO2PD3_LT % 2 2 3 !
76: CONST HO2PD3_LT : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO3PD2_D5A (Ho–Pd)

Id: phase:ho-pd:ho3pd2-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: Ho 0.6000, Pd 0.4000
Stability: stable in 1 of 1 calculated diagram(s): 300–1240 K, x(Pd) 0.4–0.4
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:ho3pd2-d5a
tdb: tdb:HoPd-00Du.tdb:HO3PD2_D5A

TDB models of HO3PD2_D5A (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO3PD2_D5A, type code %, sha256 52adcba39cc7336f…

55: PHASE HO3PD2_D5A % 2 3 2 !
56: CONST HO3PD2_D5A : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO3PD4 (Ho–Pd)

Id: phase:ho-pd:ho3pd4; status assigned
Structure: Pd4Pu3 · hR14 · R-3 (148); type st:pd4pu3-hr14; tier B: DFT-supported (unique MP + OQMD match); confidence high
Stoichiometry: Ho 0.4286, Pd 0.5714
Stability: stable in 1 of 1 calculated diagram(s): 300–1700 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:ho-pd:ho3pd4
mp: mp:mp-aaackvlm
oqmd: oqmd:oqmd-1437082
tdb: tdb:HoPd-00Du.tdb:HO3PD4

TDB models of HO3PD4 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO3PD4, type code %, sha256 52adcba39cc7336f…

70: PHASE HO3PD4 % 2 3 4 !
71: CONST HO3PD4 : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HO5PD2 (Ho–Pd)

Id: phase:ho-pd:ho5pd2; 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
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: Ho 0.7143, Pd 0.2857
Stability: stable in 1 of 1 calculated diagram(s): 300–1220 K
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:ho5pd2
tdb: tdb:HoPd-00Du.tdb:HO5PD2

TDB models of HO5PD2 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HO5PD2, type code %, sha256 52adcba39cc7336f…

50: PHASE HO5PD2 % 2 5 2 !
51: CONST HO5PD2 : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HOPD_B2 (Ho–Pd)

Id: phase:ho-pd:hopd-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): 940–1750 K, x(Pd) 0.49–0.49
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:hopd-b2
tdb: tdb:HoPd-00Du.tdb:HOPD_B2

TDB models of HOPD_B2 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HOPD_B2, type code %, sha256 52adcba39cc7336f…

65: PHASE HOPD_B2 % 2 1 1 !
66: CONST HOPD_B2 : HO : HO PD% : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HOPD_B27 (Ho–Pd)

Id: phase:ho-pd:hopd-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): 300–970 K, x(Pd) 0.5–0.5
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:hopd-b27
tdb: tdb:HoPd-00Du.tdb:HOPD_B27

TDB models of HOPD_B27 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HOPD_B27, type code %, sha256 52adcba39cc7336f…

60: PHASE HOPD_B27 % 2 1 1 !
61: CONST HOPD_B27 : HO : HO PD% : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HOPD3_L12 (Ho–Pd)

Id: phase:ho-pd:hopd3-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): 300–2001.54 K, x(Pd) 0.75–0.79332
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:hopd3-l12
tdb: tdb:HoPd-00Du.tdb:HOPD3_L12

TDB models of HOPD3_L12 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HOPD3_L12, type code %, sha256 52adcba39cc7336f…

90: PHASE HOPD3_L12 % 2 1 3 !
91: CONST HOPD3_L12 : HO% PD : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

HOPD7 (Ho–Pd)

Id: phase:ho-pd:hopd7; status needs_review
No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token; sgte_mmc2_row_incomplete
Candidate (sgte_mmc2): (HoPd7) — Hallstedt 2025 mmc2 row for HOPD7: HoPd7
Stoichiometry: Ho 0.1250, Pd 0.8750
Stability: stable in 1 of 1 calculated diagram(s): 300–748.03 K, x(Pd) 0.875–0.875
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:hopd7
tdb: tdb:HoPd-00Du.tdb:HOPD7

TDB models of HOPD7 (1): PHASE and CONSTITUENT statements as written

HoPd-00Du.tdb: HOPD7, type code %, sha256 52adcba39cc7336f…

95: PHASE HOPD7 % 2 1 7 !
96: CONST HOPD7 : HO : PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
assessment that models this phase

LIQUID (Ho–Pd)

Id: phase:ho-pd:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1180–2500 K, x(Pd) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ho-pd:liquid
tdb: tdb:HoPd-00Du.tdb:LIQUID

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

HoPd-00Du.tdb: LIQUID, type code %, sha256 52adcba39cc7336f…

30: PHASE LIQUID:L % 1 1 !
31: CONST LIQUID:L : HO PD : !

Example references (1 of 1; assessments first):

doi:10.1515/ijmr-2000-911114 Z. Du, H. Yang, T. Liu, Z. Metallkd., 91, 963-66(2000).
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}
}