Cu–Pt phases

6 phases (tier A 4, liquid 1, needs_review 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 · Cu–Pt system page · Markdown · field reference

Phases of the Cu–Pt system (6)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:cu-pt:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
CUPT_L11 phase:cu-pt:cupt-l11	CuPt · L1_1 · hR2 · R-3m (166)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1094.25 K, x(Pt) 0.36146–0.68399	5	1
FCC_4SL phase:cu-pt:fcc-4sl		needs_review	stable in 1 of 1 calculated diagram(s): 300–2041.5 K, x(Pt) 0–1	15	1
FCC_A1 phase:cu-pt:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2030 K, x(Pt) 0–0.98	0	2
HCP_A3 phase:cu-pt: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-pt:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1357.77–2500 K, x(Pt) 0–1	0	1

BCC_A2 (Cu–Pt)

Id: phase:cu-pt: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:cu-pt:bcc-a2
tdb: tdb:CuPt-06Abe.tdb:BCC_A2

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

CuPt-06Abe.tdb: BCC_A2, type code %B, sha256 22e617239e135878…

53: PHASE BCC_A2 %B 2 1 3 !
54: CONST BCC_A2 : CU PT : VA : !

Example references (1 of 1; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models this phase

CUPT_L11 (Cu–Pt)

Id: phase:cu-pt:cupt-l11; status assigned
Structure: CuPt · L1_1 · hR2 · R-3m (166); type st:l1-1-cupt-hr2; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in CuPt-06Abe.tdb also describes the disordered state
Stability: stable in 1 of 1 calculated diagram(s): 300–1094.25 K, x(Pt) 0.36146–0.68399
Literature: 5 values (5 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-pt:cupt-l11
paper: paper:10.1361/105497196x92736:L11-CuPt
tdb: tdb:CuPt-06Abe.tdb:CUPT_L11

TDB models of CUPT_L11 (1): PHASE and CONSTITUENT statements as written

CuPt-06Abe.tdb: CUPT_L11, type code %, sha256 22e617239e135878…

63: PHASE CUPT_L11 % 2 0.5 0.5 !
64: CONST CUPT_L11 : CU% PT : CU PT% : !

Example references (5 of 5; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models this phase; reports values for this phase
doi:10.1016/0001-6160(62)90102-5 R Oriani, W.K Murphy, Thermodynamics of ordering alloys—IV heats of formation of some alloys of transition metals, Acta Metallurgica 10, 879-885 (1962).
cited as the source of values for this phase
doi:10.1103/physrevb.39.5792 Satoshi Takizawa, Kiyoyuki Terakura, Tetsuo Mohri, Electronic theory for phase stability of nineABbinary alloys, withA=Ni, Pd, or Pt andB=Cu, Ag, or Au, Phys. Rev. B 39, 5792-5797 (1989).
cited as the source of values for this phase
doi:10.1103/physrevb.44.512 Z. W. Lu, S.-H. Wei, Alex Zunger, S. Frota-Pessoa, L. G. Ferreira, First-principles statistical mechanics of structural stability of intermetallic compounds, Phys. Rev. B 44, 512-544 (1991).
cited as the source of values for this phase
doi:10.1143/jpsj.65.2178 Satoshi Takizawa, A New Phase of Cu–Pt Alloy – Theoretical Prediction and Experimental Support, J. Phys. Soc. Jpn. 65, 2178-2181 (1996).
cited as the source of values for this phase

FCC_4SL (Cu–Pt)

Id: phase:cu-pt:fcc-4sl; status needs_review
No structure assigned. Why: assessment_declared_blocked_by:order_disorder_ambiguity; order_disorder_ambiguity:CuPt-06Abe.tdb_model_is_partitioned; sgte_mmc2_row_disagrees_with_name:FCC_4SL; unrecognised_name_tokens:4SL
Candidate (dft_mp): Pm-3m (221) — on-hull MP Cu3Pt at x(PT)=0.2500
Candidate (dft_mp): R-3m (166) — on-hull MP CuPt at x(PT)=0.5000
Candidate (dft_mp): Fm-3m (225) — on-hull MP CuPt7 at x(PT)=0.8750
Candidate (dft_oqmd): R-3m (166) — on-hull OQMD Cu1 Pt1 at x(PT)=0.5000
Candidate (dft_oqmd): Pm-3m (221) — on-hull OQMD Cu1 Pt3 at x(PT)=0.7500
Candidate (dft_oqmd): Fm-3m (225) — on-hull OQMD Cu1 Pt7 at x(PT)=0.8750
Candidate (dft_oqmd): Pm-3m (221) — on-hull OQMD Cu3 Pt1 at x(PT)=0.2500
Candidate (dft_oqmd): Fm-3m (225) — on-hull OQMD Cu7 Pt1 at x(PT)=0.1250
Stability: stable in 1 of 1 calculated diagram(s): 300–2041.5 K, x(Pt) 0–1
Literature: 15 values (15 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:cu-pt:fcc-4sl
paper: paper:10.1361/105497196x92736:L10-CuPt, paper:10.1361/105497196x92736:L12-Cu3Pt, paper:10.1361/105497196x92736:L12-CuPt3
tdb: tdb:CuPt-06Abe.tdb:FCC_4SL

TDB models of FCC_4SL (1): PHASE and CONSTITUENT statements as written

CuPt-06Abe.tdb: FCC_4SL, type code %AY, sha256 22e617239e135878…

48: PHASE FCC_4SL %AY 5 0.25 0.25 0.25 0.25 1 !
49: CONST FCC_4SL : CU% PT : CU PT% : CU PT% : CU PT% : VA :  !

Example references (5 of 5; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models this phase; reports values for this phase
doi:10.1103/physrevb.39.5792 Satoshi Takizawa, Kiyoyuki Terakura, Tetsuo Mohri, Electronic theory for phase stability of nineABbinary alloys, withA=Ni, Pd, or Pt andB=Cu, Ag, or Au, Phys. Rev. B 39, 5792-5797 (1989).
cited as the source of values for this phase
doi:10.1103/physrevb.44.512 Z. W. Lu, S.-H. Wei, Alex Zunger, S. Frota-Pessoa, L. G. Ferreira, First-principles statistical mechanics of structural stability of intermetallic compounds, Phys. Rev. B 44, 512-544 (1991).
cited as the source of values for this phase
doi:10.1103/physrevlett.88.255506 G. H. Jóhannesson, T. Bligaard, A. V. Ruban, H. L. Skriver, K. W. Jacobsen, J. K. Nørskov, Combined Electronic Structure and Evolutionary Search Approach to Materials Design, Phys. Rev. Lett. 88 (2002).
cited as the source of values for this phase
doi:10.1143/jpsj.65.2178 Satoshi Takizawa, A New Phase of Cu–Pt Alloy – Theoretical Prediction and Experimental Support, J. Phys. Soc. Jpn. 65, 2178-2181 (1996).
cited as the source of values for this phase

FCC_A1 (Cu–Pt)

Id: phase:cu-pt: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): 300–2030 K, x(Pt) 0–0.98
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:cu-pt:fcc-a1
tdb: tdb:CuPt-06Abe.tdb:A1_FCC, tdb:CuPt-06Abe.tdb:FCC_A1

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

CuPt-06Abe.tdb: A1_FCC, type code %A, sha256 22e617239e135878…

43: PHASE A1_FCC %A 2 1 1 !
44: CONST A1_FCC : CU PT : VA : !

CuPt-06Abe.tdb: FCC_A1, type code %A, sha256 22e617239e135878…

38: PHASE FCC_A1 %A 2 1 1 !
39: CONST FCC_A1 : CU PT : VA : !

Example references (1 of 1; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models this phase

HCP_A3 (Cu–Pt)

Id: phase:cu-pt: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:cu-pt:hcp-a3
tdb: tdb:CuPt-06Abe.tdb:HCP_A3

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

CuPt-06Abe.tdb: HCP_A3, type code %A, sha256 22e617239e135878…

58: PHASE HCP_A3 %A 2 1 0.5 !
59: CONST HCP_A3 : CU PT : VA : !

Example references (1 of 1; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models this phase

LIQUID (Cu–Pt)

Id: phase:cu-pt:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1357.77–2500 K, x(Pt) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:cu-pt:liquid
tdb: tdb:CuPt-06Abe.tdb:LIQUID

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

CuPt-06Abe.tdb: LIQUID, type code %, sha256 22e617239e135878…

33: PHASE LIQUID:L % 1 1 !
34: CONST LIQUID:L : CU PT : !

Example references (1 of 1; assessments first):

doi:10.1361/105497196X92736 T. Abe, B. Sundman, H. Onodera, J. Phase Equilib. Diffus., 27, 5-13(2006).
assessment that models 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}
}