Fe–Lu phases

10 phases (tier A 5, tier C 2, liquid 1, needs_review 2); 10 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 · Fe–Lu system page · Markdown · field reference

Phases of the Fe–Lu system (10)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:fe-lu:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1822.47 K, x(Lu) 0–0	5	2
FCC_A1 phase:fe-lu:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 1184.81–1667.47 K, x(Lu) 0–0	4	2
FE17LU2 phase:fe-lu:fe17lu2		needs_review	stable in 1 of 1 calculated diagram(s): 300–1590.27 K, x(Lu) 0.10526–0.10526	12	1
FE17LU2_HT phase:fe-lu:fe17lu2-ht		needs_review	stable in 1 of 1 calculated diagram(s): 1190.62–1593.22 K, x(Lu) 0.08224–0.10076	9	1
FE17LU2_LT phase:fe-lu:fe17lu2-lt	Ni17Th2 · hP38 · P6_3/mmc (194)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 360.42–1192.32 K, x(Lu) 0.08975–0.10526	12	1
FE23LU6_D8A phase:fe-lu:fe23lu6-d8a	Mn23Th6 · D8_a · cF116 · Fm-3m (225)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1560.91 K, x(Lu) 0.2069–0.2069	5	2
FE2LU_C15 phase:fe-lu:fe2lu-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1619.28 K, x(Lu) 0.33333–0.33333	8	2
FE3LU phase:fe-lu:fe3lu	Ni3Pu · hR12 · R-3m (166)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 2 of 2 calculated diagram(s): 300–1581.75 K, x(Lu) 0.25–0.25	22	2
HCP_A3 phase:fe-lu:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–2499.64 K, x(Lu) 0.99739–1	2	2
LIQUID phase:fe-lu:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 1237.63–2500 K, x(Lu) 0–1	22	2

BCC_A2 (Fe–Lu)

Id: phase:fe-lu:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stoichiometry: Fe 1.0000
Stability: stable in 2 of 2 calculated diagram(s): 300–1822.47 K, x(Lu) 0–0
Literature: 5 values (5 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-lu:bcc-a2
paper: paper:10.1016/j.calphad.2014.01.003:δFe
tdb: tdb:FeLu-14Kar.tdb:BCC_A2, tdb:FeLu-23Ye.tdb:BCC_A2

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

FeLu-14Kar.tdb: BCC_A2, type code %B, sha256 93d8c09f43286312…

38: PHASE BCC_A2 %B 2 1 3 !
39: CONST BCC_A2 : FE : VA : !

FeLu-23Ye.tdb: BCC_A2, type code %B, sha256 2a24b752097da078…

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

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

FCC_A1 (Fe–Lu)

Id: phase:fe-lu:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stoichiometry: Fe 1.0000
Stability: stable in 2 of 2 calculated diagram(s): 1184.81–1667.47 K, x(Lu) 0–0
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-lu:fcc-a1
paper: paper:10.1016/j.calphad.2014.01.003:γFe
tdb: tdb:FeLu-14Kar.tdb:FCC_A1, tdb:FeLu-23Ye.tdb:FCC_A1

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

FeLu-14Kar.tdb: FCC_A1, type code %A, sha256 93d8c09f43286312…

33: PHASE FCC_A1 %A 2 1 1 !
34: CONST FCC_A1 : FE : VA : !

FeLu-23Ye.tdb: FCC_A1, type code %A, sha256 2a24b752097da078…

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

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

FE17LU2 (Fe–Lu)

Id: phase:fe-lu:fe17lu2; status needs_review
No structure assigned. Why: no_on_hull_entry_in_both; no_structure_token
Candidate (tdb_comment): Ni17Th2 · hP38 · P6_3/mmc — FeLu-23Ye.tdb: 'Prototype Ni17Th2 (hP38, P6_3/mmc)'
Stoichiometry: Fe 0.8947, Lu 0.1053
Stability: stable in 1 of 1 calculated diagram(s): 300–1590.27 K, x(Lu) 0.10526–0.10526
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:fe-lu:fe17lu2
paper: paper:10.20517/jmi.2023.08:Fe17Lu2
tdb: tdb:FeLu-23Ye.tdb:FE17LU2

TDB models of FE17LU2 (1): PHASE and CONSTITUENT statements as written

FeLu-23Ye.tdb: FE17LU2, type code %A, sha256 2a24b752097da078…

44: PHASE FE17LU2 %A 2 17 2 !
45: CONST FE17LU2 : FE : LU : !

Example references (1 of 1; assessments first):

doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
reports values for this phase

FE17LU2_HT (Fe–Lu)

Id: phase:fe-lu:fe17lu2-ht; status needs_review
No structure assigned. Why: no_structure_token; off_stoichiometric_model; sgte_mmc2_row_incomplete
Candidate (literature_printed): (Fe17Lu2-ht) · ? — printed with a label mapped to this phase
Candidate (sgte_mmc2): (Fe17Lu2-ht) — Hallstedt 2025 mmc2 row for FE17LU2_HT: Fe17Lu2 (high T)
Stability: stable in 1 of 1 calculated diagram(s): 1190.62–1593.22 K, x(Lu) 0.08224–0.10076
Literature: 9 values (7 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-lu:fe17lu2-ht
paper: paper:10.1016/j.calphad.2014.01.003:Fe17Lu2_HT, paper:10.1016/j.calphad.2014.01.003:αFe17Lu2_HT
tdb: tdb:FeLu-14Kar.tdb:FE17LU2_HT

TDB models of FE17LU2_HT (1): PHASE and CONSTITUENT statements as written

FeLu-14Kar.tdb: FE17LU2_HT, type code %, sha256 93d8c09f43286312…

53: PHASE FE17LU2_HT % 2 17 2 !
54: CONST FE17LU2_HT : FE : FE LU% : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

FE17LU2_LT (Fe–Lu)

Id: phase:fe-lu:fe17lu2-lt; 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_structure_token, off_stoichiometric_model); structure as stated in the SGTE crystallographic table for this phase name and system
Stability: stable in 1 of 1 calculated diagram(s): 360.42–1192.32 K, x(Lu) 0.08975–0.10526
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:fe-lu:fe17lu2-lt
paper: paper:10.1016/j.calphad.2014.01.003:Fe17Lu2_LT
tdb: tdb:FeLu-14Kar.tdb:FE17LU2_LT

TDB models of FE17LU2_LT (1): PHASE and CONSTITUENT statements as written

FeLu-14Kar.tdb: FE17LU2_LT, type code %A, sha256 93d8c09f43286312…

48: PHASE FE17LU2_LT %A 2 17 2 !
49: CONST FE17LU2_LT : FE : FE LU% : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase
doi:10.1016/0364-5916(91)90030-n A.T. Dinsdale, SGTE data for pure elements, Calphad 15, 317-425 (1991).
cited as the source of values for this phase

FE23LU6_D8A (Fe–Lu)

Id: phase:fe-lu:fe23lu6-d8a; status assigned
Structure: Mn23Th6 · D8_a · cF116 · Fm-3m (225); type st:d8-a-mn23th6-cf116; tier A: standard phase name; confidence high
Stoichiometry: Fe 0.7931, Lu 0.2069
Stability: stable in 2 of 2 calculated diagram(s): 300–1560.91 K, x(Lu) 0.2069–0.2069
Literature: 5 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-lu:fe23lu6-d8a
paper: paper:10.1016/j.calphad.2014.01.003:Fe23Lu6
tdb: tdb:FeLu-14Kar.tdb:FE23LU6_D8A, tdb:FeLu-23Ye.tdb:FE23LU6_D8A

TDB models of FE23LU6_D8A (2): PHASE and CONSTITUENT statements as written

FeLu-14Kar.tdb: FE23LU6_D8A, type code %A, sha256 93d8c09f43286312…

58: PHASE FE23LU6_D8A %A 2 23 6 !
59: CONST FE23LU6_D8A : FE : LU : !

FeLu-23Ye.tdb: FE23LU6_D8A, type code %A, sha256 2a24b752097da078…

49: PHASE FE23LU6_D8A %A 2 23 6 !
50: CONST FE23LU6_D8A : FE : LU : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

FE2LU_C15 (Fe–Lu)

Id: phase:fe-lu:fe2lu-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaaadqt and oqmd-30221, space group 227
Stoichiometry: Fe 0.6667, Lu 0.3333
Stability: stable in 2 of 2 calculated diagram(s): 300–1619.28 K, x(Lu) 0.33333–0.33333
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:fe-lu:fe2lu-c15
mp: mp:mp-aaaaadqt
oqmd: oqmd:oqmd-30221
paper: paper:10.1016/j.calphad.2014.01.003:Fe2Lu
tdb: tdb:FeLu-14Kar.tdb:FE2LU_C15, tdb:FeLu-23Ye.tdb:FE2LU_C15

TDB models of FE2LU_C15 (2): PHASE and CONSTITUENT statements as written

FeLu-14Kar.tdb: FE2LU_C15, type code %A, sha256 93d8c09f43286312…

68: PHASE FE2LU_C15 %A 2 2 1 !
69: CONST FE2LU_C15 : FE : LU : !

FeLu-23Ye.tdb: FE2LU_C15, type code %A, sha256 2a24b752097da078…

59: PHASE FE2LU_C15 %A 2 2 1 !
60: CONST FE2LU_C15 : FE : LU : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

FE3LU (Fe–Lu)

Id: phase:fe-lu:fe3lu; status assigned
Structure: Ni3Pu · hR12 · R-3m (166); type st:ni3pu-hr12; 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_mp, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Fe 0.7500, Lu 0.2500
Stability: stable in 2 of 2 calculated diagram(s): 300–1581.75 K, x(Lu) 0.25–0.25
Literature: 22 values (22 accepted) from 2 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:fe-lu:fe3lu
paper: paper:10.1016/j.calphad.2014.01.003:Fe3Lu, paper:10.20517/jmi.2023.08:Fe3Lu
tdb: tdb:FeLu-14Kar.tdb:FE3LU, tdb:FeLu-23Ye.tdb:FE3LU

TDB models of FE3LU (2): PHASE and CONSTITUENT statements as written

FeLu-14Kar.tdb: FE3LU, type code %A, sha256 93d8c09f43286312…

63: PHASE FE3LU %A 2 3 1 !
64: CONST FE3LU : FE : LU : !

FeLu-23Ye.tdb: FE3LU, type code %A, sha256 2a24b752097da078…

54: PHASE FE3LU %A 2 3 1 !
55: CONST FE3LU : FE : LU : !

Example references (3 of 3; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase
doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
reports values for this phase
doi:10.1016/0364-5916(91)90030-n A.T. Dinsdale, SGTE data for pure elements, Calphad 15, 317-425 (1991).
cited as the source of values for this phase

HCP_A3 (Fe–Lu)

Id: phase:fe-lu: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): 300–2499.64 K, x(Lu) 0.99739–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:fe-lu:hcp-a3
paper: paper:10.1016/j.calphad.2014.01.003:(Lu)
tdb: tdb:FeLu-14Kar.tdb:HCP_A3, tdb:FeLu-23Ye.tdb:HCP_A3

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

FeLu-14Kar.tdb: HCP_A3, type code %A, sha256 93d8c09f43286312…

43: PHASE HCP_A3 %A 2 1 0.5 !
44: CONST HCP_A3 : FE LU% : VA : !

FeLu-23Ye.tdb: HCP_A3, type code %A, sha256 2a24b752097da078…

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

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase

LIQUID (Fe–Lu)

Id: phase:fe-lu:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 1237.63–2500 K, x(Lu) 0–1
Literature: 22 values (20 accepted) from 2 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:fe-lu:liquid
paper: paper:10.1016/j.calphad.2014.01.003:L, paper:10.1016/j.calphad.2014.01.003:Liq, paper:10.20517/jmi.2023.08:L
tdb: tdb:FeLu-14Kar.tdb:LIQUID, tdb:FeLu-23Ye.tdb:LIQUID

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

FeLu-14Kar.tdb: LIQUID, type code %, sha256 93d8c09f43286312…

28: PHASE LIQUID:L % 1 1 !
29: CONST LIQUID:L : FE LU : !

FeLu-23Ye.tdb: LIQUID, type code %, sha256 2a24b752097da078…

24: PHASE LIQUID:L % 1 1 !
25: CONST LIQUID:L : FE LU : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2014.01.003 S. Kardellass, C. Servant, N. Selhaoui, A. Iddaoudi, Thermodynamic evaluations of the iron–lutetium and iron–thulium systems, Calphad 46, 42-54 (2014).
assessment that models this phase; reports values for this phase
doi:10.20517/jmi.2023.08 Hongjian Ye, Maohua Rong, Qing Chen, Qingrong Yao, Jiang Wang, Guanghui Rao et al., Assessment of phase equilibria and thermodynamic properties in the Fe-RE (RE = rare earth metals) binary systems, J Mater Inf 3 (2023).
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}
}