Al–Er phases

10 phases (tier A 6, tier B 1, tier C 2, liquid 1); 9 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 · Al–Er system page · Markdown · field reference

Phases of the Al–Er system (10)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
AL2ER_C15 phase:al-er:al2er-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1731.83 K, x(Er) 0.31411–0.35442	0	2
AL2ER3 phase:al-er:al2er3	Al2Zr3 · tP20 · P4_2/mnm (136)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 2 of 2 calculated diagram(s): 300–1357.07 K, x(Er) 0.6–0.6	1	2
AL3ER phase:al-er:al3er	Al3Ho · hR20 · R-3m (166)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–1383.85 K, x(Er) 0.25–0.25	0	1
AL3ER_L12 phase:al-er:al3er-l12	AuCu3 · L1_2 · cP4 · Pm-3m (221)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1277.87 K, x(Er) 0.25–0.25	0	1
ALER phase:al-er:aler	AlDy · oP16 · Pbcm (57)	tier B: DFT-supported (unique MP + OQMD match)	stable in 2 of 2 calculated diagram(s): 300–1410.22 K, x(Er) 0.5–0.5	3	2
ALER2_C37 phase:al-er:aler2-c37	Co2Si · C37 · oP12 · Pnma (62)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–1329.58 K, x(Er) 0.66667–0.66667	0	2
BCC_A2 phase:al-er:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 2 calculated diagram(s)	0	2
FCC_A1 phase:al-er:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–949.47 K, x(Er) 0–0	0	2
HCP_A3 phase:al-er:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–2499.68 K, x(Er) 0.99947–1	0	2
LIQUID phase:al-er:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 912.03–2500 K, x(Er) 0–1	0	2

AL2ER_C15 (Al–Er)

Id: phase:al-er:al2er-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in AlEr-02Cac.tdb also describes the disordered state
Caveat: partitioned order/disorder model in AlEr-22Xu.tdb also describes the disordered state
Stability: stable in 2 of 2 calculated diagram(s): 300–1731.83 K, x(Er) 0.31411–0.35442
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-er:al2er-c15
tdb: tdb:AlEr-02Cac.tdb:AL2ER_C15, tdb:AlEr-22Xu.tdb:AL2ER_C15

TDB models of AL2ER_C15 (2): PHASE and CONSTITUENT statements as written

AlEr-02Cac.tdb: AL2ER_C15, type code %, sha256 263c39948e36dfd7…

64: PHASE AL2ER_C15 % 2 2 1 !
65: CONST AL2ER_C15 : AL% ER : AL ER% : !

AlEr-22Xu.tdb: AL2ER_C15, type code %, sha256 fa89fd62a159d002…

47: PHASE AL2ER_C15 % 2 2 1 !
48: CONST AL2ER_C15 : AL% ER : AL ER% : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

AL2ER3 (Al–Er)

Id: phase:al-er:al2er3; status assigned
Structure: Al2Zr3 · tP20 · P4_2/mnm (136); type st:al2zr3-tp20; 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: Al 0.4000, Er 0.6000
Stability: stable in 2 of 2 calculated diagram(s): 300–1357.07 K, x(Er) 0.6–0.6
Literature: 1 values (1 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:al-er:al2er3
paper: paper:10.1016/j.calphad.2008.05.002:Al2Er3
tdb: tdb:AlEr-02Cac.tdb:AL2ER3, tdb:AlEr-22Xu.tdb:AL2ER3

TDB models of AL2ER3 (2): PHASE and CONSTITUENT statements as written

AlEr-02Cac.tdb: AL2ER3, type code %, sha256 263c39948e36dfd7…

74: PHASE AL2ER3 % 2 2 3 !
75: CONST AL2ER3 : AL : ER : !

AlEr-22Xu.tdb: AL2ER3, type code %, sha256 fa89fd62a159d002…

57: PHASE AL2ER3 % 2 2 3 !
58: CONST AL2ER3 : AL : ER : !

Example references (3 of 3; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase
doi:10.1016/j.calphad.2008.05.002 L.G. Zhang, L.B. Liu, G.X. Huang, H.Y. Qi, B.R. Jia, Z.P. Jin, Thermodynamic assessment of the Al–Cu–Er system, Calphad 32, 527-534 (2008).
reports values for this phase

AL3ER (Al–Er)

Id: phase:al-er:al3er; status assigned
Structure: Al3Ho · hR20 · R-3m (166); type st:al3ho-hr20; 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, polymorph_family:other phases of this system have the same composition); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Al 0.7500, Er 0.2500
Stability: stable in 1 of 1 calculated diagram(s): 300–1383.85 K, x(Er) 0.25–0.25
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:al-er:al3er
tdb: tdb:AlEr-22Xu.tdb:AL3ER

TDB models of AL3ER (1): PHASE and CONSTITUENT statements as written

AlEr-22Xu.tdb: AL3ER, type code %, sha256 fa89fd62a159d002…

42: PHASE AL3ER % 2 3 1 !
43: CONST AL3ER : AL : ER : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase

AL3ER_L12 (Al–Er)

Id: phase:al-er:al3er-l12; status assigned
Structure: AuCu3 · L1_2 · cP4 · Pm-3m (221); type st:l1-2-aucu3-cp4; tier A: standard phase name; confidence high
Stoichiometry: Al 0.7500, Er 0.2500
Stability: stable in 1 of 1 calculated diagram(s): 300–1277.87 K, x(Er) 0.25–0.25
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:al-er:al3er-l12
tdb: tdb:AlEr-02Cac.tdb:AL3ER_L12

TDB models of AL3ER_L12 (1): PHASE and CONSTITUENT statements as written

AlEr-02Cac.tdb: AL3ER_L12, type code %, sha256 263c39948e36dfd7…

59: PHASE AL3ER_L12 % 2 3 1 !
60: CONST AL3ER_L12 : AL : ER : !

Example references (1 of 1; assessments first):

doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

ALER (Al–Er)

Id: phase:al-er:aler; status assigned
Structure: AlDy · oP16 · Pbcm (57); type st:aldy-op16; tier B: DFT-supported (unique MP + OQMD match); confidence high
Stoichiometry: Al 0.5000, Er 0.5000
Stability: stable in 2 of 2 calculated diagram(s): 300–1410.22 K, x(Er) 0.5–0.5
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (6): corpus: corpus:phase:al-er:aler
mp: mp:mp-aaacpqmt
oqmd: oqmd:oqmd-658342
paper: paper:10.1016/j.calphad.2008.05.002:AlEr
tdb: tdb:AlEr-02Cac.tdb:ALER, tdb:AlEr-22Xu.tdb:ALER

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

AlEr-02Cac.tdb: ALER, type code %, sha256 263c39948e36dfd7…

69: PHASE ALER % 2 1 1 !
70: CONST ALER : AL : ER : !

AlEr-22Xu.tdb: ALER, type code %, sha256 fa89fd62a159d002…

52: PHASE ALER % 2 1 1 !
53: CONST ALER : AL : ER : !

Example references (3 of 3; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase
doi:10.1016/j.calphad.2008.05.002 L.G. Zhang, L.B. Liu, G.X. Huang, H.Y. Qi, B.R. Jia, Z.P. Jin, Thermodynamic assessment of the Al–Cu–Er system, Calphad 32, 527-534 (2008).
reports values for this phase

ALER2_C37 (Al–Er)

Id: phase:al-er:aler2-c37; status assigned
Structure: Co2Si · C37 · oP12 · Pnma (62); type st:c37-co2si-op12; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaacktmh and oqmd-1436042, space group 62
Stoichiometry: Al 0.3333, Er 0.6667
Stability: stable in 2 of 2 calculated diagram(s): 300–1329.58 K, x(Er) 0.66667–0.66667
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:al-er:aler2-c37
mp: mp:mp-aaacktmh
oqmd: oqmd:oqmd-1436042
tdb: tdb:AlEr-02Cac.tdb:ALER2_C37, tdb:AlEr-22Xu.tdb:ALER2_C37

TDB models of ALER2_C37 (2): PHASE and CONSTITUENT statements as written

AlEr-02Cac.tdb: ALER2_C37, type code %, sha256 263c39948e36dfd7…

79: PHASE ALER2_C37 % 2 1 2 !
80: CONST ALER2_C37 : AL : ER : !

AlEr-22Xu.tdb: ALER2_C37, type code %, sha256 fa89fd62a159d002…

62: PHASE ALER2_C37 % 2 1 2 !
63: CONST ALER2_C37 : AL : ER : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

BCC_A2 (Al–Er)

Id: phase:al-er: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:al-er:bcc-a2
tdb: tdb:AlEr-02Cac.tdb:BCC_A2, tdb:AlEr-22Xu.tdb:BCC_A2

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

AlEr-02Cac.tdb: BCC_A2, type code %, sha256 263c39948e36dfd7…

49: PHASE BCC_A2 % 2 1 3 !
50: CONST BCC_A2 : AL ER : VA : !

AlEr-22Xu.tdb: BCC_A2, type code %B, sha256 fa89fd62a159d002…

32: PHASE BCC_A2 %B 2 1 3 !
33: CONST BCC_A2 : AL ER : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

FCC_A1 (Al–Er)

Id: phase:al-er: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): 300–949.47 K, x(Er) 0–0
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-er:fcc-a1
tdb: tdb:AlEr-02Cac.tdb:FCC_A1, tdb:AlEr-22Xu.tdb:FCC_A1

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

AlEr-02Cac.tdb: FCC_A1, type code %, sha256 263c39948e36dfd7…

34: PHASE FCC_A1 % 2 1 1 !
35: CONST FCC_A1 : AL% ER : VA : !

AlEr-22Xu.tdb: FCC_A1, type code %A, sha256 fa89fd62a159d002…

27: PHASE FCC_A1 %A 2 1 1 !
28: CONST FCC_A1 : AL% ER : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

HCP_A3 (Al–Er)

Id: phase:al-er: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): 300–2499.68 K, x(Er) 0.99947–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-er:hcp-a3
tdb: tdb:AlEr-02Cac.tdb:HCP_A3, tdb:AlEr-22Xu.tdb:HCP_A3

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

AlEr-02Cac.tdb: HCP_A3, type code %, sha256 263c39948e36dfd7…

54: PHASE HCP_A3 % 2 1 0.5 !
55: CONST HCP_A3 : AL ER% : VA : !

AlEr-22Xu.tdb: HCP_A3, type code %A, sha256 fa89fd62a159d002…

37: PHASE HCP_A3 %A 2 1 0.5 !
38: CONST HCP_A3 : AL ER% : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
assessment that models this phase

LIQUID (Al–Er)

Id: phase:al-er:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 912.03–2500 K, x(Er) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-er:liquid
tdb: tdb:AlEr-02Cac.tdb:LIQUID, tdb:AlEr-22Xu.tdb:LIQUID

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

AlEr-02Cac.tdb: LIQUID, type code %, sha256 263c39948e36dfd7…

29: PHASE LIQUID:L % 1 1 !
30: CONST LIQUID:L : AL ER : !

AlEr-22Xu.tdb: LIQUID, type code %, sha256 fa89fd62a159d002…

22: PHASE LIQUID:L % 1 1 !
23: CONST LIQUID:L : AL ER : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2022.102482 L. Xu, X. Shi, D. Xia, D. Huang, H. Tang, Calphad, 79, 102482(2022).
assessment that models this phase
doi:10.1361/105497102770332199 G. Cacciamani, A. Saccone, S. De Negri, R. Ferro, J. Phase Equilib., 23, 38-50(2002).
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}
}