Co–Sc phases

8 phases (tier A 5, liquid 1, needs_review 2); 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 · Co–Sc system page · Markdown · field reference

Phases of the Co–Sc system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:co-sc:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 1601.82–2499.32 K, x(Sc) 0.99862–1	2	1
CO2SC_C15 phase:co-sc:co2sc-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1792.32 K, x(Sc) 0.30741–0.36353	6	1
COSC_B2 phase:co-sc:cosc-b2		needs_review	stable in 1 of 1 calculated diagram(s): 300–1322.24 K, x(Sc) 0.48–0.48	4	1
COSC2_C16 phase:co-sc:cosc2-c16	Al2Cu · C16 · tI12 · I4/mcm (140)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1113.73 K, x(Sc) 0.66667–0.66667	6	1
COSC3 phase:co-sc:cosc3		needs_review	stable in 1 of 1 calculated diagram(s): 300–1092.49 K, x(Sc) 0.77–0.77	4	1
FCC_A1 phase:co-sc:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 694.47–1770.85 K, x(Sc) 0–0.00915	4	1
HCP_A3 phase:co-sc:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1812.96 K, x(Sc) 0–1	2	1
LIQUID phase:co-sc:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1024.14–2500 K, x(Sc) 0–1	18	1

BCC_A2 (Co–Sc)

Id: phase:co-sc: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): 1601.82–2499.32 K, x(Sc) 0.99862–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:bcc-a2
paper: paper:10.1016/j.jallcom.2007.11.069:βSc
tdb: tdb:CoSc-08Liu.tdb:BCC_A2

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

CoSc-08Liu.tdb: BCC_A2, type code %B, sha256 b016d43f8f1436b7…

37: PHASE BCC_A2 %B 2 1 3 !
38: CONST BCC_A2 : CO SC% : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

CO2SC_C15 (Co–Sc)

Id: phase:co-sc:co2sc-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in CoSc-08Liu.tdb also describes the disordered state
Stability: stable in 1 of 1 calculated diagram(s): 300–1792.32 K, x(Sc) 0.30741–0.36353
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:co2sc-c15
paper: paper:10.1016/j.jallcom.2007.11.069:Co2Sc
tdb: tdb:CoSc-08Liu.tdb:CO2SC_C15

TDB models of CO2SC_C15 (1): PHASE and CONSTITUENT statements as written

CoSc-08Liu.tdb: CO2SC_C15, type code %, sha256 b016d43f8f1436b7…

47: PHASE CO2SC_C15 % 2 2 1 !
48: CONST CO2SC_C15 : CO% SC : CO SC% : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

COSC_B2 (Co–Sc)

Id: phase:co-sc:cosc-b2; status needs_review
No structure assigned. Why: assessment_declared_blocked_by:stoichiometry_contradicts_B2; stoichiometry_contradicts_B2:CoSc-08Liu.tdb
Candidate (literature_printed): CsCl · cP2 — printed with a label mapped to this phase
Candidate (name_token): CsCl · B2 · cP2 · Pm-3m (221) — Strukturbericht/word 'B2' in the TDB name
Candidate (sgte_mmc2): CsCl · B2 · cP2 · Pm-3m (221) — Hallstedt 2025 mmc2 row for COSC_B2: CoSc
Candidate (tdb_comment): CsCl · cP2 · Pm-3m — CoSc-08Liu.tdb: 'Prototype CsCl (cP2, Pm-3m)'
Stoichiometry: Co 0.5200, Sc 0.4800
Stability: stable in 1 of 1 calculated diagram(s): 300–1322.24 K, x(Sc) 0.48–0.48
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:cosc-b2
paper: paper:10.1016/j.jallcom.2007.11.069:CoSc
tdb: tdb:CoSc-08Liu.tdb:COSC_B2

TDB models of COSC_B2 (1): PHASE and CONSTITUENT statements as written

CoSc-08Liu.tdb: COSC_B2, type code %, sha256 b016d43f8f1436b7…

52: PHASE COSC_B2 % 2 0.52 0.48 !
53: CONST COSC_B2 : CO : SC : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

COSC2_C16 (Co–Sc)

Id: phase:co-sc:cosc2-c16; status assigned
Structure: Al2Cu · C16 · tI12 · I4/mcm (140); type st:c16-al2cu-ti12; tier A: standard phase name; confidence high
Stoichiometry: Co 0.3333, Sc 0.6667
Stability: stable in 1 of 1 calculated diagram(s): 300–1113.73 K, x(Sc) 0.66667–0.66667
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:cosc2-c16
paper: paper:10.1016/j.jallcom.2007.11.069:CoSc2
tdb: tdb:CoSc-08Liu.tdb:COSC2_C16

TDB models of COSC2_C16 (1): PHASE and CONSTITUENT statements as written

CoSc-08Liu.tdb: COSC2_C16, type code %, sha256 b016d43f8f1436b7…

57: PHASE COSC2_C16 % 2 1 2 !
58: CONST COSC2_C16 : CO : SC : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

COSC3 (Co–Sc)

Id: phase:co-sc:cosc3; status needs_review
No structure assigned. Why: assessment_declared_compound_differs_from_model_composition; no_on_hull_entry_in_both; no_structure_token
Candidate (literature_printed): CoSc3 · oP32 — printed with a label mapped to this phase
Candidate (sgte_mmc2): CoSc3 · oP32 · Pnma (62) — Hallstedt 2025 mmc2 row for COSC3: CoSc3
Candidate (tdb_comment): CoSc3 · oP32 · Pnma — CoSc-08Liu.tdb: 'Prototype CoSc3 (oP32, Pnma)'
Stoichiometry: Co 0.2300, Sc 0.7700
Stability: stable in 1 of 1 calculated diagram(s): 300–1092.49 K, x(Sc) 0.77–0.77
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:cosc3
paper: paper:10.1016/j.jallcom.2007.11.069:CoSc3
tdb: tdb:CoSc-08Liu.tdb:COSC3

TDB models of COSC3 (1): PHASE and CONSTITUENT statements as written

CoSc-08Liu.tdb: COSC3, type code %, sha256 b016d43f8f1436b7…

62: PHASE COSC3 % 2 0.23 0.77 !
63: CONST COSC3 : CO : SC : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

FCC_A1 (Co–Sc)

Id: phase:co-sc: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): 694.47–1770.85 K, x(Sc) 0–0.00915
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:fcc-a1
paper: paper:10.1016/j.jallcom.2007.11.069:αCo
tdb: tdb:CoSc-08Liu.tdb:FCC_A1

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

CoSc-08Liu.tdb: FCC_A1, type code %A, sha256 b016d43f8f1436b7…

32: PHASE FCC_A1 %A 2 1 1 !
33: CONST FCC_A1 : CO% SC : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

HCP_A3 (Co–Sc)

Id: phase:co-sc: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): 300–1812.96 K, x(Sc) 0–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:hcp-a3
paper: paper:10.1016/j.jallcom.2007.11.069:αSc
tdb: tdb:CoSc-08Liu.tdb:HCP_A3

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

CoSc-08Liu.tdb: HCP_A3, type code %A, sha256 b016d43f8f1436b7…

42: PHASE HCP_A3 %A 2 1 0.5 !
43: CONST HCP_A3 : CO% SC% : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports values for this phase

LIQUID (Co–Sc)

Id: phase:co-sc:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1024.14–2500 K, x(Sc) 0–1
Literature: 18 values (18 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-sc:liquid
paper: paper:10.1016/j.jallcom.2007.11.069:L
tdb: tdb:CoSc-08Liu.tdb:LIQUID

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

CoSc-08Liu.tdb: LIQUID, type code %, sha256 b016d43f8f1436b7…

27: PHASE LIQUID:L % 1 1 !
28: CONST LIQUID:L : CO SC : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.11.069 X.J. Liu, P. Yu, C.P. Wang, K. Ishida, Thermodynamic evaluation of the Co–Sc and Fe–Sc systems, Journal of Alloys and Compounds 466, 169-175 (2008).
assessment that models this phase; reports 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}
}