Cu–Th phases

8 phases (tier A 5, tier B 1, liquid 1, needs_review 1); 7 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 · Cu–Th system page · Markdown · field reference

Phases of the Cu–Th system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:cu-th:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 1633.42–3999.24 K, x(Th) 0.99871–1	0	1
CU18TH5 phase:cu-th:cu18th5		needs_review	stable in 1 of 1 calculated diagram(s): 300–1325 K, x(Th) 0.21739–0.21739	6	1
CU2TH_C32 phase:cu-th:cu2th-c32	AlB2 · C32 · hP3 · P6/mmm (191)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1287.39 K, x(Th) 0.33333–0.33333	6	1
CU6TH phase:cu-th:cu6th	CeCu6 · oP28 · Pnma (62)	tier B: DFT-supported (unique MP + OQMD match)	stable in 1 of 1 calculated diagram(s): 967.14–1328.51 K, x(Th) 0.14286–0.14286	6	1
CUTH2_C16 phase:cu-th:cuth2-c16	Al2Cu · C16 · tI12 · I4/mcm (140)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1277.37 K, x(Th) 0.66667–0.66667	6	1
FCC_A1 phase:cu-th:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1633.42 K, x(Th) 0–1	4	1
HCP_A3 phase:cu-th: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:cu-th:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1157.84–4000 K, x(Th) 0–1	18	1

BCC_A2 (Cu–Th)

Id: phase:cu-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): 1633.42–3999.24 K, x(Th) 0.99871–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:cu-th:bcc-a2
tdb: tdb:CuTh-08Wan.tdb:BCC_A2

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

CuTh-08Wan.tdb: BCC_A2, type code %B, sha256 8ae901d23dd6c3e4…

34: PHASE BCC_A2 %B 2 1 3 !
35: CONST BCC_A2 : CU TH% : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase

CU18TH5 (Cu–Th)

Id: phase:cu-th:cu18th5; 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): Ag51Gd14 · hP68 — printed with a label mapped to this phase
Candidate (sgte_mmc2): Ag51Gd14 · hP68 · P6/m (175) — Hallstedt 2025 mmc2 row for CU18TH5: Cu51Th14
Candidate (tdb_comment): Ag51Gd14 · hP68 · P6/m — CuTh-08Wan.tdb: 'Prototype Ag51Gd14 (hP68, P6/m)'
Stoichiometry: Cu 0.7826, Th 0.2174
Stability: stable in 1 of 1 calculated diagram(s): 300–1325 K, x(Th) 0.21739–0.21739
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-th:cu18th5
paper: paper:10.1016/j.jallcom.2007.04.017:Cu3.6Th
tdb: tdb:CuTh-08Wan.tdb:CU18TH5

TDB models of CU18TH5 (1): PHASE and CONSTITUENT statements as written

CuTh-08Wan.tdb: CU18TH5, type code %, sha256 8ae901d23dd6c3e4…

49: PHASE CU18TH5 % 2 18 5 !
50: CONST CU18TH5 : CU : TH : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
cited as the source of values for this phase

CU2TH_C32 (Cu–Th)

Id: phase:cu-th:cu2th-c32; status assigned
Structure: AlB2 · C32 · hP3 · P6/mmm (191); type st:c32-alb2-hp3; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaaacaz and oqmd-88945, space group 191
Stoichiometry: Cu 0.6667, Th 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–1287.39 K, x(Th) 0.33333–0.33333
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:cu-th:cu2th-c32
mp: mp:mp-aaaaacaz
oqmd: oqmd:oqmd-88945
paper: paper:10.1016/j.jallcom.2007.04.017:Cu2Th
tdb: tdb:CuTh-08Wan.tdb:CU2TH_C32

TDB models of CU2TH_C32 (1): PHASE and CONSTITUENT statements as written

CuTh-08Wan.tdb: CU2TH_C32, type code %, sha256 8ae901d23dd6c3e4…

54: PHASE CU2TH_C32 % 2 2 1 !
55: CONST CU2TH_C32 : CU : TH : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
cited as the source of values for this phase

CU6TH (Cu–Th)

Id: phase:cu-th:cu6th; status assigned
Structure: CeCu6 · oP28 · Pnma (62); type st:cecu6-op28; tier B: DFT-supported (unique MP + OQMD match); confidence high
Stoichiometry: Cu 0.8571, Th 0.1429
Stability: stable in 1 of 1 calculated diagram(s): 967.14–1328.51 K, x(Th) 0.14286–0.14286
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:cu-th:cu6th
mp: mp:mp-aaaaaszq
oqmd: oqmd:oqmd-19585
paper: paper:10.1016/j.jallcom.2007.04.017:Cu6Th
tdb: tdb:CuTh-08Wan.tdb:CU6TH

TDB models of CU6TH (1): PHASE and CONSTITUENT statements as written

CuTh-08Wan.tdb: CU6TH, type code %, sha256 8ae901d23dd6c3e4…

44: PHASE CU6TH % 2 6 1 !
45: CONST CU6TH : CU : TH : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
cited as the source of values for this phase

CUTH2_C16 (Cu–Th)

Id: phase:cu-th:cuth2-c16; status assigned
Structure: Al2Cu · C16 · tI12 · I4/mcm (140); type st:c16-al2cu-ti12; tier A: standard phase name; confidence high
Stoichiometry: Cu 0.3333, Th 0.6667
Stability: stable in 1 of 1 calculated diagram(s): 300–1277.37 K, x(Th) 0.66667–0.66667
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-th:cuth2-c16
paper: paper:10.1016/j.jallcom.2007.04.017:CuTh2
tdb: tdb:CuTh-08Wan.tdb:CUTH2_C16

TDB models of CUTH2_C16 (1): PHASE and CONSTITUENT statements as written

CuTh-08Wan.tdb: CUTH2_C16, type code %, sha256 8ae901d23dd6c3e4…

59: PHASE CUTH2_C16 % 2 1 2 !
60: CONST CUTH2_C16 : CU : TH : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
cited as the source of values for this phase

FCC_A1 (Cu–Th)

Id: phase:cu-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): 300–1633.42 K, x(Th) 0–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:cu-th:fcc-a1
paper: paper:10.1016/j.jallcom.2007.04.017:(Cu), paper:10.1016/j.jallcom.2007.04.017:(αTh)
tdb: tdb:CuTh-08Wan.tdb:FCC_A1

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

CuTh-08Wan.tdb: FCC_A1, type code %A, sha256 8ae901d23dd6c3e4…

29: PHASE FCC_A1 %A 2 1 1 !
30: CONST FCC_A1 : CU% TH% : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
cited as the source of values for this phase

HCP_A3 (Cu–Th)

Id: phase:cu-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
Stoichiometry: Cu 1.0000
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:cu-th:hcp-a3
tdb: tdb:CuTh-08Wan.tdb:HCP_A3

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

CuTh-08Wan.tdb: HCP_A3, type code %A, sha256 8ae901d23dd6c3e4…

39: PHASE HCP_A3 %A 2 1 0.5 !
40: CONST HCP_A3 : CU : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase

LIQUID (Cu–Th)

Id: phase:cu-th:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1157.84–4000 K, x(Th) 0–1
Literature: 18 values (18 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-th:liquid
paper: paper:10.1016/j.jallcom.2007.04.017:L
tdb: tdb:CuTh-08Wan.tdb:LIQUID

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

CuTh-08Wan.tdb: LIQUID, type code %, sha256 8ae901d23dd6c3e4…

24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : CU TH : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2007.04.017 C.P. Wang, Y.F. Li, X.J. Liu, K. Ishida, Thermodynamic assessments of the Cu–Th and Mo–Th systems, Journal of Alloys and Compounds 458, 208-213 (2008).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(71)90128-7 R.J. Schiltz, E.R. Stevens, O.N. Carlson, The thorium-copper system, Journal of the Less Common Metals 25, 175-185 (1971).
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}
}