Eu–Ni phases

8 phases (tier A 5, tier C 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 · Eu–Ni system page · Markdown · field reference

Phases of the Eu–Ni system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:eu-ni:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1099.97 K, x(Ni) 0–3e-05	0	1
EU2NI17 phase:eu-ni:eu2ni17	Ni17Th2 · hP38 · P6_3/mmc (194)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–1463.99 K, x(Ni) 0.89474–0.89474	3	1
EUNI phase:eu-ni:euni		needs_review	stable in 1 of 1 calculated diagram(s): 300–1391.71 K, x(Ni) 0.5–0.5	12	1
EUNI2_C36 phase:eu-ni:euni2-c36	MgNi2 · C36 · hP24 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1353.33 K, x(Ni) 0.66667–0.66667	6	1
EUNI5_D2D phase:eu-ni:euni5-d2d	CaCu5 · D2_d · hP6 · P6/mmm (191)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1636.66 K, x(Ni) 0.83333–0.83333	13	1
FCC_A1 phase:eu-ni:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2499.49 K, x(Ni) 1–1	7	1
HCP_A3 phase:eu-ni: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:eu-ni:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1044.97–2500 K, x(Ni) 0–1	27	1

BCC_A2 (Eu–Ni)

Id: phase:eu-ni: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): 300–1099.97 K, x(Ni) 0–3e-05
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:eu-ni:bcc-a2
tdb: tdb:EuNi-16Kar.tdb:BCC_A2

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

EuNi-16Kar.tdb: BCC_A2, type code %B, sha256 921469b7e3cef2dd…

33: PHASE BCC_A2 %B 2 1 3 !
34: CONST BCC_A2 : EU% NI : VA : !

Example references (1 of 1; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase

EU2NI17 (Eu–Ni)

Id: phase:eu-ni:eu2ni17; status assigned
Structure: Ni17Th2 · hP38 · P6_3/mmc (194); type st:ni17th2-hp38; tier C: assessor-stated (Hallstedt 2025 crystallographic table); confidence assessor-stated
Structure source: B. Hallstedt, The SGTE collection of binary datasets, Calphad 89 (2025) 102833, supplementary crystallographic table (mmc2) doi:10.1016/j.calphad.2025.102833
Caveat: not certain from the name or DFT alone (no_on_hull_entry_in_both, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Eu 0.1053, Ni 0.8947
Stability: stable in 1 of 1 calculated diagram(s): 300–1463.99 K, x(Ni) 0.89474–0.89474
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:eu-ni:eu2ni17
paper: paper:10.1007/s10973-016-5380-3:Ni17Eu2
tdb: tdb:EuNi-16Kar.tdb:EU2NI17

TDB models of EU2NI17 (1): PHASE and CONSTITUENT statements as written

EuNi-16Kar.tdb: EU2NI17, type code %, sha256 921469b7e3cef2dd…

58: PHASE EU2NI17 % 2 2 17 !
59: CONST EU2NI17 : EU : NI : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
cited as the source of values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase

EUNI (Eu–Ni)

Id: phase:eu-ni:euni; status needs_review
No structure assigned. Why: no_on_hull_entry_in_mp; no_structure_token; sgte_mmc2_row_incomplete
Candidate (dft_oqmd): P63/mmc (194) — on-hull OQMD Eu1 Ni1 at x(NI)=0.5000
Candidate (literature_printed): (EuNi) · ? — printed with a label mapped to this phase
Candidate (sgte_mmc2): (EuNi) — Hallstedt 2025 mmc2 row for EUNI: EuNi
Stoichiometry: Eu 0.5000, Ni 0.5000
Stability: stable in 1 of 1 calculated diagram(s): 300–1391.71 K, x(Ni) 0.5–0.5
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:eu-ni:euni
paper: paper:10.1007/s10973-016-5380-3:NiEu
tdb: tdb:EuNi-16Kar.tdb:EUNI

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

EuNi-16Kar.tdb: EUNI, type code %, sha256 921469b7e3cef2dd…

43: PHASE EUNI % 2 1 1 !
44: CONST EUNI : EU : NI : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
cited as the source of values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase

EUNI2_C36 (Eu–Ni)

Id: phase:eu-ni:euni2-c36; status assigned
Structure: MgNi2 · C36 · hP24 · P6_3/mmc (194); type st:c36-mgni2-hp24; tier A: standard phase name; confidence high
Stoichiometry: Eu 0.3333, Ni 0.6667
Stability: stable in 1 of 1 calculated diagram(s): 300–1353.33 K, x(Ni) 0.66667–0.66667
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:eu-ni:euni2-c36
paper: paper:10.1007/s10973-016-5380-3:Ni2Eu
tdb: tdb:EuNi-16Kar.tdb:EUNI2_C36

TDB models of EUNI2_C36 (1): PHASE and CONSTITUENT statements as written

EuNi-16Kar.tdb: EUNI2_C36, type code %, sha256 921469b7e3cef2dd…

48: PHASE EUNI2_C36 % 2 1 2 !
49: CONST EUNI2_C36 : EU : NI : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
cited as the source of values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase

EUNI5_D2D (Eu–Ni)

Id: phase:eu-ni:euni5-d2d; status assigned
Structure: CaCu5 · D2_d · hP6 · P6/mmm (191); type st:d2-d-cacu5-hp6; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaabhad and oqmd-30109, space group 191
Stoichiometry: Eu 0.1667, Ni 0.8333
Stability: stable in 1 of 1 calculated diagram(s): 300–1636.66 K, x(Ni) 0.83333–0.83333
Literature: 13 values (13 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:eu-ni:euni5-d2d
mp: mp:mp-aaaabhad
oqmd: oqmd:oqmd-30109
paper: paper:10.1007/s10973-016-5380-3:Ni5Eu
tdb: tdb:EuNi-16Kar.tdb:EUNI5_D2D

TDB models of EUNI5_D2D (1): PHASE and CONSTITUENT statements as written

EuNi-16Kar.tdb: EUNI5_D2D, type code %, sha256 921469b7e3cef2dd…

53: PHASE EUNI5_D2D % 2 1 5 !
54: CONST EUNI5_D2D : EU : NI : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
cited as the source of values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase

FCC_A1 (Eu–Ni)

Id: phase:eu-ni:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stoichiometry: Ni 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–2499.49 K, x(Ni) 1–1
Literature: 7 values (7 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:eu-ni:fcc-a1
paper: paper:10.1007/s10973-016-5380-3:fcc_A1
tdb: tdb:EuNi-16Kar.tdb:FCC_A1

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

EuNi-16Kar.tdb: FCC_A1, type code %A, sha256 921469b7e3cef2dd…

28: PHASE FCC_A1 %A 2 1 1 !
29: CONST FCC_A1 : NI : VA : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
cited as the source of values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase

HCP_A3 (Eu–Ni)

Id: phase:eu-ni: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: Ni 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:eu-ni:hcp-a3
tdb: tdb:EuNi-16Kar.tdb:HCP_A3

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

EuNi-16Kar.tdb: HCP_A3, type code %A, sha256 921469b7e3cef2dd…

38: PHASE HCP_A3 %A 2 1 0.5 !
39: CONST HCP_A3 : NI : VA : !

Example references (1 of 1; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase

LIQUID (Eu–Ni)

Id: phase:eu-ni:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1044.97–2500 K, x(Ni) 0–1
Literature: 27 values (27 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:eu-ni:liquid
paper: paper:10.1007/s10973-016-5380-3:L
tdb: tdb:EuNi-16Kar.tdb:LIQUID

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

EuNi-16Kar.tdb: LIQUID, type code %, sha256 921469b7e3cef2dd…

23: PHASE LIQUID:L % 1 1 !
24: CONST LIQUID:L : EU NI : !

Example references (4 of 4; assessments first):

doi:10.1007/s10973-016-5380-3 Saïd Kardellass, Colette Servant, Najim Selhaoui, Thermodynamic description of the Ni–Yb and Ni–Eu binary systems, J Therm Anal Calorim 125, 255-269 (2016).
assessment that models this phase; reports values for this phase
doi:10.1134/s0036024414090064 V. V. Berezutskii, M. A. Shevchenko, M. I. Ivanov, V. S. Sudavtsova, Thermodynamic properties of liquid alloys Ni-Eu and Ni-Yb, Russ. J. Phys. Chem. 88, 1463-1471 (2014).
cited as the source of values for this phase
doi:10.1007/bf00819832 E. M. Savitskii, V. F. Terekhova, R. S. Torchinova, Europium alloys, Met Sci Heat Treat 9, 100-106 (1967).
cited as the source of values for this phase
doi:10.1007/bf02881420 Tung CH, Nash P. The Eu–Ni (europium–nickel) system. Bull Alloy Phase Diagr. 1989;10(2):127–9.
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}
}