Sc–Th phases

4 phases (tier A 3, liquid 1); 4 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 · Sc–Th system page · Markdown · field reference

Phases of the Sc–Th system (4)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:sc-th:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 1423.13–2022.99 K, x(Th) 0–1	7	1
FCC_A1 phase:sc-th:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1633.2 K, x(Th) 0.36725–1	2	1
HCP_A3 phase:sc-th:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1607.99 K, x(Th) 0–0.21171	3	1
LIQUID phase:sc-th:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1678.37–4000 K, x(Th) 0–1	4	1

BCC_A2 (Sc–Th)

Id: phase:sc-th: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): 1423.13–2022.99 K, x(Th) 0–1
Literature: 7 values (7 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:sc-th:bcc-a2
paper: paper:10.1016/j.jallcom.2008.02.018:(βSc, βTh), paper:10.1016/j.jallcom.2008.02.018:βSc, paper:10.1016/j.jallcom.2008.02.018:βTh
tdb: tdb:ScTh-09Liu.tdb:BCC_A2

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

ScTh-09Liu.tdb: BCC_A2, type code %B, sha256 8d3c6dbf1d99af30…

32: PHASE BCC_A2 %B 2 1 3 !
33: CONST BCC_A2 : SC TH : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2008.02.018 X.J. Liu, S.L. Wang, C.P. Wang, Thermodynamic assessments of the Sc–M (M: Ag, B and Th) systems, Journal of Alloys and Compounds 469, 186-192 (2009).
assessment that models this phase; reports values for this phase

FCC_A1 (Sc–Th)

Id: phase:sc-th: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): 300–1633.2 K, x(Th) 0.36725–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:sc-th:fcc-a1
paper: paper:10.1016/j.jallcom.2008.02.018:αTh
tdb: tdb:ScTh-09Liu.tdb:FCC_A1

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

ScTh-09Liu.tdb: FCC_A1, type code %A, sha256 8d3c6dbf1d99af30…

27: PHASE FCC_A1 %A 2 1 1 !
28: CONST FCC_A1 : SC TH% : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2008.02.018 X.J. Liu, S.L. Wang, C.P. Wang, Thermodynamic assessments of the Sc–M (M: Ag, B and Th) systems, Journal of Alloys and Compounds 469, 186-192 (2009).
assessment that models this phase; reports values for this phase

HCP_A3 (Sc–Th)

Id: phase:sc-th: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): 300–1607.99 K, x(Th) 0–0.21171
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:sc-th:hcp-a3
paper: paper:10.1016/j.jallcom.2008.02.018:αSc
tdb: tdb:ScTh-09Liu.tdb:HCP_A3

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

ScTh-09Liu.tdb: HCP_A3, type code %A, sha256 8d3c6dbf1d99af30…

37: PHASE HCP_A3 %A 2 1 0.5 !
38: CONST HCP_A3 : SC% TH : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2008.02.018 X.J. Liu, S.L. Wang, C.P. Wang, Thermodynamic assessments of the Sc–M (M: Ag, B and Th) systems, Journal of Alloys and Compounds 469, 186-192 (2009).
assessment that models this phase; reports values for this phase

LIQUID (Sc–Th)

Id: phase:sc-th:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1678.37–4000 K, x(Th) 0–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:sc-th:liquid
paper: paper:10.1016/j.jallcom.2008.02.018:L
tdb: tdb:ScTh-09Liu.tdb:LIQUID

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

ScTh-09Liu.tdb: LIQUID, type code %, sha256 8d3c6dbf1d99af30…

22: PHASE LIQUID:L % 1 1 !
23: CONST LIQUID:L : SC TH : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2008.02.018 X.J. Liu, S.L. Wang, C.P. Wang, Thermodynamic assessments of the Sc–M (M: Ag, B and Th) systems, Journal of Alloys and Compounds 469, 186-192 (2009).
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}
}