Cu–Ge phases

9 phases (tier A 5, 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 · Cu–Ge system page · Markdown · field reference

Phases of the Cu–Ge system (9)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
DIAMOND_A4 phase:cu-ge:a4-diamond	C (diamond) · A4 · cF8 · Fd-3m (227)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1211.4 K, x(Ge) 1–1	4	2
BCC_A2 phase:cu-ge:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 2 calculated diagram(s)	0	2
CU3GE phase:cu-ge:cu3ge		needs_review	stable in 1 of 1 calculated diagram(s): 300–1017.11 K, x(Ge) 0.25–0.25	0	1
CU3GE_D018 phase:cu-ge:cu3ge-d018		needs_review	stable in 1 of 1 calculated diagram(s): 822.46–1022.22 K, x(Ge) 0.235–0.235	10	1
CU3GE_D03 phase:cu-ge:cu3ge-d03		needs_review	stable in 1 of 1 calculated diagram(s): 884.79–970.46 K, x(Ge) 0.265–0.265	8	1
CU3GE_D0A phase:cu-ge:cu3ge-d0a	beta-Cu3Ti · D0_a · oP8 · Pmmn (59)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–947.61 K, x(Ge) 0.25–0.25	6	1
FCC_A1 phase:cu-ge:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1360.77 K, x(Ge) 0–0.11795	2	2
HCP_A3 phase:cu-ge:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1097.53 K, x(Ge) 0.09624–0.1857	6	2
LIQUID phase:cu-ge:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 908.02–2500 K, x(Ge) 0–1	10	2

DIAMOND_A4 (Cu–Ge)

Id: phase:cu-ge:a4-diamond; status assigned
Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type st:a4-c-diamond-cf8; tier A: standard phase name; confidence high
Stoichiometry: Ge 1.0000
Stability: stable in 2 of 2 calculated diagram(s): 300–1211.4 K, x(Ge) 1–1
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:cu-ge:a4-diamond, corpus:phase:cu-ge:diamond-a4
paper: paper:10.1016/j.jallcom.2010.05.077:(Ge)
tdb: tdb:CuGe-10Wan.tdb:DIAMOND_A4, tdb:CuGe-Rand.tdb:DIAMOND_A4

TDB models of DIAMOND_A4 (2): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: DIAMOND_A4, type code %, sha256 af99f4c24e73a88e…

40: PHASE DIAMOND_A4 % 1 1 !
41: CONST DIAMOND_A4 : GE : !

CuGe-Rand.tdb: DIAMOND_A4, type code %, sha256 39799a146bda7651…

44: PHASE DIAMOND_A4 % 1 1 !
45: CONST DIAMOND_A4 : GE : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

BCC_A2 (Cu–Ge)

Id: phase:cu-ge: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 2 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-ge:bcc-a2
tdb: tdb:CuGe-10Wan.tdb:BCC_A2, tdb:CuGe-Rand.tdb:BCC_A2

TDB models of BCC_A2 (2): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: BCC_A2, type code %B, sha256 af99f4c24e73a88e…

30: PHASE BCC_A2 %B 2 1 3 !
31: CONST BCC_A2 : CU GE : VA : !

CuGe-Rand.tdb: BCC_A2, type code %B, sha256 39799a146bda7651…

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

Example references (1 of 1; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase

CU3GE (Cu–Ge)

Id: phase:cu-ge:cu3ge; status needs_review
No structure assigned. Why: no_structure_token; polymorph_family:other phases of this system have the same composition
Candidate (dft_mp): Pmmn (59) — on-hull MP Cu3Ge at x(GE)=0.2500
Candidate (dft_oqmd): Pmmn (59) — on-hull OQMD Cu3 Ge1 at x(GE)=0.2500
Candidate (tdb_comment): BiF3 · cF16 · Fm-3m — CuGe-Rand.tdb: 'Prototype BiF3 (cF16, Fm-3m), theta (high-T), also Cu5Ge2'
Candidate (tdb_comment): Na3As · hP8 · P6_3/mmc — CuGe-Rand.tdb: 'Prototype Na3As (hP8, P6_3/mmc), epsilon (high-T)'
Candidate (tdb_comment): beta-Cu3Ti · oP8 · Pmmn — CuGe-Rand.tdb: 'Prototype beta-Cu3Ti (oP8, Pmmn), eta (low-T)'
Stoichiometry: Cu 0.7500, Ge 0.2500
Stability: stable in 1 of 1 calculated diagram(s): 300–1017.11 K, x(Ge) 0.25–0.25
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:cu-ge:cu3ge
tdb: tdb:CuGe-Rand.tdb:CU3GE

TDB models of CU3GE (1): PHASE and CONSTITUENT statements as written

CuGe-Rand.tdb: CU3GE, type code %, sha256 39799a146bda7651…

51: PHASE CU3GE % 2 3 1 !
52: CONST CU3GE : CU : GE : !

CU3GE_D018 (Cu–Ge)

Id: phase:cu-ge:cu3ge-d018; status needs_review
No structure assigned. Why: assessment_declared_blocked_by:stoichiometry_contradicts_D0_18; stoichiometry_contradicts_D0_18:CuGe-10Wan.tdb
Candidate (literature_printed): Na3As · hP8 — printed with a label mapped to this phase
Candidate (name_token): Na3As · D0_18 · hP8 · P6_3/mmc (194) — Strukturbericht/word 'D018' in the TDB name
Candidate (sgte_mmc2): Na3As · D0_18 · hP8 · P6_3/mmc (194) — Hallstedt 2025 mmc2 row for CU3GE_D018: Cu3Ge (epsilon, high-T)
Candidate (tdb_comment): Na3As · hP8 · P6_3/mmc — CuGe-10Wan.tdb: 'Prototype Na3As (hP8, P6_3/mmc), epsilon (high-T)'
Stoichiometry: Cu 0.7650, Ge 0.2350
Stability: stable in 1 of 1 calculated diagram(s): 822.46–1022.22 K, x(Ge) 0.235–0.235
Literature: 10 values (10 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-ge:cu3ge-d018
paper: paper:10.1016/j.jallcom.2010.05.077:ε-Cu0.765Ge0.235
tdb: tdb:CuGe-10Wan.tdb:CU3GE_D018

TDB models of CU3GE_D018 (1): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: CU3GE_D018, type code %, sha256 af99f4c24e73a88e…

45: PHASE CU3GE_D018 % 2 0.765 0.235 !
46: CONST CU3GE_D018 : CU : GE : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

CU3GE_D03 (Cu–Ge)

Id: phase:cu-ge:cu3ge-d03; status needs_review
No structure assigned. Why: assessment_declared_blocked_by:stoichiometry_contradicts_D0_3; stoichiometry_contradicts_D0_3:CuGe-10Wan.tdb
Candidate (literature_printed): BiF3 · cF16 — printed with a label mapped to this phase
Candidate (name_token): BiF3 · D0_3 · cF16 · Fm-3m (225) — Strukturbericht/word 'D03' in the TDB name
Candidate (sgte_mmc2): BiF3 · D0_3 · cF16 · Fm-3m (225) — Hallstedt 2025 mmc2 row for CU3GE_D03: Cu3Ge (theta, high-T, Cu5Ge2)
Candidate (tdb_comment): BiF3 · cF16 · Fm-3m — CuGe-10Wan.tdb: 'Prototype BiF3 (cF16, Fm-3m), theta (high-T), also Cu5Ge2'
Stoichiometry: Cu 0.7350, Ge 0.2650
Stability: stable in 1 of 1 calculated diagram(s): 884.79–970.46 K, x(Ge) 0.265–0.265
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-ge:cu3ge-d03
paper: paper:10.1016/j.jallcom.2010.05.077:θ-Cu0.735Ge0.265
tdb: tdb:CuGe-10Wan.tdb:CU3GE_D03

TDB models of CU3GE_D03 (1): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: CU3GE_D03, type code %, sha256 af99f4c24e73a88e…

55: PHASE CU3GE_D03 % 2 0.735 0.265 !
56: CONST CU3GE_D03 : CU : GE : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

CU3GE_D0A (Cu–Ge)

Id: phase:cu-ge:cu3ge-d0a; status assigned
Structure: beta-Cu3Ti · D0_a · oP8 · Pmmn (59); type st:d0-a-beta-cu3ti-op8; tier A: standard phase name; confidence high
Stoichiometry: Cu 0.7500, Ge 0.2500
Stability: stable in 1 of 1 calculated diagram(s): 300–947.61 K, x(Ge) 0.25–0.25
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-ge:cu3ge-d0a
paper: paper:10.1016/j.jallcom.2010.05.077:η-Cu0.75Ge0.25
tdb: tdb:CuGe-10Wan.tdb:CU3GE_D0A

TDB models of CU3GE_D0A (1): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: CU3GE_D0A, type code %, sha256 af99f4c24e73a88e…

50: PHASE CU3GE_D0A % 2 0.75 0.25 !
51: CONST CU3GE_D0A : CU : GE : !

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

FCC_A1 (Cu–Ge)

Id: phase:cu-ge: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 2 of 2 calculated diagram(s): 300–1360.77 K, x(Ge) 0–0.11795
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:cu-ge:fcc-a1
paper: paper:10.1016/j.jallcom.2010.05.077:fcc
tdb: tdb:CuGe-10Wan.tdb:FCC_A1, tdb:CuGe-Rand.tdb:FCC_A1

TDB models of FCC_A1 (2): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: FCC_A1, type code %A, sha256 af99f4c24e73a88e…

25: PHASE FCC_A1 %A 2 1 1 !
26: CONST FCC_A1 : CU% GE : VA : !

CuGe-Rand.tdb: FCC_A1, type code %A, sha256 39799a146bda7651…

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

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

HCP_A3 (Cu–Ge)

Id: phase:cu-ge: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 2 of 2 calculated diagram(s): 300–1097.53 K, x(Ge) 0.09624–0.1857
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:cu-ge:hcp-a3
paper: paper:10.1016/j.jallcom.2010.05.077:hcp
tdb: tdb:CuGe-10Wan.tdb:HCP_A3, tdb:CuGe-Rand.tdb:HCP_A3

TDB models of HCP_A3 (2): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: HCP_A3, type code %A, sha256 af99f4c24e73a88e…

35: PHASE HCP_A3 %A 2 1 0.5 !
36: CONST HCP_A3 : CU GE : VA : !

CuGe-Rand.tdb: HCP_A3, type code %A, sha256 39799a146bda7651…

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

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
cited as the source of values for this phase

LIQUID (Cu–Ge)

Id: phase:cu-ge:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 908.02–2500 K, x(Ge) 0–1
Literature: 10 values (10 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:cu-ge:liquid
paper: paper:10.1016/j.jallcom.2010.05.077:L
tdb: tdb:CuGe-10Wan.tdb:LIQUID, tdb:CuGe-Rand.tdb:LIQUID

TDB models of LIQUID (2): PHASE and CONSTITUENT statements as written

CuGe-10Wan.tdb: LIQUID, type code %, sha256 af99f4c24e73a88e…

20: PHASE LIQUID:L % 1 1 !
21: CONST LIQUID:L : CU GE : !

CuGe-Rand.tdb: LIQUID, type code %, sha256 39799a146bda7651…

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

Example references (2 of 2; assessments first):

doi:10.1016/j.jallcom.2010.05.077 J. Wang, S. Jin, C. Leinenbach, A. Jacot, Thermodynamic assessment of the Cu–Ge binary system, Journal of Alloys and Compounds 504, 159-165 (2010).
assessment that models this phase; reports values for this phase
doi:10.1007/bf02874979 R.W. Olesinski, G.J. Abbaschian, Bull. Alloy Phase diagrams 7 (1986) 28.
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}
}