Bi–Rh phases

10 phases (tier A 5, tier B 1, liquid 1, needs_review 3); 8 stable in a calculated diagram. Structure types are assigned only when the stored evidence supports an assignment under the stated tier rules (tier A: standard phase name; tier B: unique Materials Project + OQMD on-hull match, DFT-supported; tier C: one structure stated by the assessment's crystallographic table, assessor-stated); other phases list candidates and are marked needs_review. Stability is from phase diagrams calculated with pycalphad from the SGTE binary collection (evidence class: model).

Data: interactive registry · full JSON · Bi–Rh system page · Markdown · field reference

Phases of the Bi–Rh system (10)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
RHOMBOHEDRAL_A7 phase:bi-rh: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(Rh) 0–0	4	1
BCC_A2 phase:bi-rh:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
BI2RH_HT phase:bi-rh:bi2rh-ht		needs_review	stable in 1 of 1 calculated diagram(s): 703.05–1058.19 K, x(Rh) 0.33333–0.33333	16	1
BI2RH_LT phase:bi-rh:bi2rh-lt		needs_review	stable in 1 of 1 calculated diagram(s): 300–703.05 K, x(Rh) 0.33333–0.33333	6	1
BI4RH phase:bi-rh:bi4rh	Bi4Rh · cI120 · Ia-3d (230)	tier B: DFT-supported (unique MP + OQMD match)	stable in 1 of 1 calculated diagram(s): 300–734.56 K, x(Rh) 0.2–0.2	10	1
BI55RH45_B31 phase:bi-rh:bi55rh45-b31		needs_review	stable in 1 of 1 calculated diagram(s): 300–755.1 K, x(Rh) 0.45–0.45	4	1
BIRH_B81 phase:bi-rh:birh-b81	NiAs · B8_1 · hP4 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1252.99 K, x(Rh) 0.46135–0.5	10	1
FCC_A1 phase:bi-rh:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–3999.4 K, x(Rh) 0.98969–1	4	1
HCP_A3 phase:bi-rh: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-rh:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 540.16–4000 K, x(Rh) 0–1	16	1

RHOMBOHEDRAL_A7 (Bi–Rh)

Id: phase:bi-rh: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
Stoichiometry: Bi 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–544.55 K, x(Rh) 0–0
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:bi-rh:a7-rhombohedral, corpus:phase:bi-rh:rhombohedral-a7
paper: paper:10.1007/s11669-020-00854-w:Bi
tdb: tdb:BiRh-20Zob.tdb:RHOMBOHEDRAL_A7

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

BiRh-20Zob.tdb: RHOMBOHEDRAL_A7, type code %, sha256 32604489a1ba7475…

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

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

BCC_A2 (Bi–Rh)

Id: phase:bi-rh: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

Names (2): corpus: corpus:phase:bi-rh:bcc-a2
tdb: tdb:BiRh-20Zob.tdb:BCC_A2

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

BiRh-20Zob.tdb: BCC_A2, type code %B, sha256 32604489a1ba7475…

35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : BI RH : VA : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase

BI2RH_HT (Bi–Rh)

Id: phase:bi-rh:bi2rh-ht; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
Candidate (dft_mp): P2_1/c (14) — on-hull MP Bi2Rh at x(RH)=0.3333
Candidate (dft_oqmd): P21/c (14) — on-hull OQMD Bi2 Rh1 at x(RH)=0.3333
Candidate (sgte_mmc2): Bi2Rh-ht · aP12 · P-1 (2) — Hallstedt 2025 mmc2 row for BI2RH_HT: Bi2Rh-ht
Candidate (tdb_comment): Bi2Rh-ht · aP12 · P-1 — BiRh-20Zob.tdb: 'Prototype Bi2Rh-ht (aP12, P-1)'
Stoichiometry: Bi 0.6667, Rh 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 703.05–1058.19 K, x(Rh) 0.33333–0.33333
Literature: 16 values (16 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:bi2rh-ht
paper: paper:10.1007/s11669-020-00854-w:Bi2Rh_HT
tdb: tdb:BiRh-20Zob.tdb:BI2RH_HT

TDB models of BI2RH_HT (1): PHASE and CONSTITUENT statements as written

BiRh-20Zob.tdb: BI2RH_HT, type code %, sha256 32604489a1ba7475…

60: PHASE BI2RH_HT % 2 2 1 !
61: CONST BI2RH_HT : BI : RH : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

BI2RH_LT (Bi–Rh)

Id: phase:bi-rh:bi2rh-lt; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
Candidate (dft_mp): P2_1/c (14) — on-hull MP Bi2Rh at x(RH)=0.3333
Candidate (dft_oqmd): P21/c (14) — on-hull OQMD Bi2 Rh1 at x(RH)=0.3333
Candidate (sgte_mmc2): CoSb2 · mP12 · P2_1/c (14) — Hallstedt 2025 mmc2 row for BI2RH_LT: Bi2Rh-lt
Candidate (tdb_comment): CoSb2 · mP12 · P2_1/c — BiRh-20Zob.tdb: 'Prototype CoSb2 (mP12, P2_1/c)'
Stoichiometry: Bi 0.6667, Rh 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–703.05 K, x(Rh) 0.33333–0.33333
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:bi2rh-lt
paper: paper:10.1007/s11669-020-00854-w:Bi2Rh_LT
tdb: tdb:BiRh-20Zob.tdb:BI2RH_LT

TDB models of BI2RH_LT (1): PHASE and CONSTITUENT statements as written

BiRh-20Zob.tdb: BI2RH_LT, type code %, sha256 32604489a1ba7475…

55: PHASE BI2RH_LT % 2 2 1 !
56: CONST BI2RH_LT : BI : RH : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

BI4RH (Bi–Rh)

Id: phase:bi-rh:bi4rh; status assigned
Structure: Bi4Rh · cI120 · Ia-3d (230); type st:bi4rh-ci120; tier B: DFT-supported (unique MP + OQMD match); confidence high
Stoichiometry: Bi 0.8000, Rh 0.2000
Stability: stable in 1 of 1 calculated diagram(s): 300–734.56 K, x(Rh) 0.2–0.2
Literature: 10 values (10 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:bi-rh:bi4rh
mp: mp:mp-aaaabtbv
oqmd: oqmd:oqmd-55228
paper: paper:10.1007/s11669-020-00854-w:Bi4Rh, paper:10.1007/s11669-020-00854-w:Ri4Rh
tdb: tdb:BiRh-20Zob.tdb:BI4RH

TDB models of BI4RH (1): PHASE and CONSTITUENT statements as written

BiRh-20Zob.tdb: BI4RH, type code %, sha256 32604489a1ba7475…

50: PHASE BI4RH % 2 4 1 !
51: CONST BI4RH : BI : RH : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

BI55RH45_B31 (Bi–Rh)

Id: phase:bi-rh:bi55rh45-b31; status needs_review
No structure assigned. Why: assessment_declared_blocked_by:stoichiometry_contradicts_B31; stoichiometry_contradicts_B31:BiRh-20Zob.tdb
Candidate (literature_printed): MnP · oP8 — printed with a label mapped to this phase
Candidate (name_token): MnP · B31 · oP8 · Pnma (62) — Strukturbericht/word 'B31' in the TDB name
Candidate (sgte_mmc2): MnP · B31 · oP8 · Pnma (62) — Hallstedt 2025 mmc2 row for BI55RH45_B31: Bi55Rh45
Candidate (tdb_comment): MnP · oP8 · Pnma — BiRh-20Zob.tdb: 'Prototype MnP (oP8, Pnma)'
Stoichiometry: Bi 0.5500, Rh 0.4500
Stability: stable in 1 of 1 calculated diagram(s): 300–755.1 K, x(Rh) 0.45–0.45
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:bi55rh45-b31
paper: paper:10.1007/s11669-020-00854-w:Bi55Rh45
tdb: tdb:BiRh-20Zob.tdb:BI55RH45_B31

TDB models of BI55RH45_B31 (1): PHASE and CONSTITUENT statements as written

BiRh-20Zob.tdb: BI55RH45_B31, type code %, sha256 32604489a1ba7475…

65: PHASE BI55RH45_B31 % 2 0.55 0.45 !
66: CONST BI55RH45_B31 : BI : RH : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase

BIRH_B81 (Bi–Rh)

Id: phase:bi-rh:birh-b81; status assigned
Structure: NiAs · B8_1 · hP4 · P6_3/mmc (194); type st:b8-1-nias-hp4; tier A: standard phase name; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–1252.99 K, x(Rh) 0.46135–0.5
Literature: 10 values (10 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:birh-b81
paper: paper:10.1007/s11669-020-00854-w:BiRh
tdb: tdb:BiRh-20Zob.tdb:BIRH_B81

TDB models of BIRH_B81 (1): PHASE and CONSTITUENT statements as written

BiRh-20Zob.tdb: BIRH_B81, type code %, sha256 32604489a1ba7475…

70: PHASE BIRH_B81 % 2 1 1 !
71: CONST BIRH_B81 : BI : BI RH% : !

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

FCC_A1 (Bi–Rh)

Id: phase:bi-rh: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): 300–3999.4 K, x(Rh) 0.98969–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:fcc-a1
paper: paper:10.1007/s11669-020-00854-w:Rh
tdb: tdb:BiRh-20Zob.tdb:FCC_A1

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

BiRh-20Zob.tdb: FCC_A1, type code %A, sha256 32604489a1ba7475…

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

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
cited as the source of values for this phase

HCP_A3 (Bi–Rh)

Id: phase:bi-rh: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 1 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:bi-rh:hcp-a3
tdb: tdb:BiRh-20Zob.tdb:HCP_A3

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

BiRh-20Zob.tdb: HCP_A3, type code %A, sha256 32604489a1ba7475…

40: PHASE HCP_A3 %A 2 1 0.5 !
41: CONST HCP_A3 : BI RH : VA: !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase

LIQUID (Bi–Rh)

Id: phase:bi-rh:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 540.16–4000 K, x(Rh) 0–1
Literature: 16 values (16 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:bi-rh:liquid
paper: paper:10.1007/s11669-020-00854-w:L
tdb: tdb:BiRh-20Zob.tdb:LIQUID

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

BiRh-20Zob.tdb: LIQUID, type code %, sha256 32604489a1ba7475…

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

Example references (2 of 2; assessments first):

doi:10.1007/s11669-020-00854-w Ondřej Zobač, Aleš Kroupa, The Thermodynamic Assessment of the Binary System Bi-Rh, J. Phase Equilib. Diffus. 41, 900-906 (2020).
assessment that models this phase; reports values for this phase
doi:10.1007/s11669-010-9660-5 H.J. Okamoto, Bi-Rh (Bismuth-Rhodium), J. Phase Equilib. Differ., 2010, 31, p 204
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). 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}
}