Al–Se phases

6 phases (tier A 4, tier C 1, liquid 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 · Al–Se system page · Markdown · field reference

Phases of the Al–Se system (6)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
HEXAGONAL_A8 phase:al-se:a8-hexagonal	gamma-Se · A8 · hP3 · P3_121 (152)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–494 K, x(Se) 1–1	2	1
AL2SE3 phase:al-se:al2se3	beta-Ga2Se3 · mC20 · Cc (9)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–1207.32 K, x(Se) 0.6–0.6	13	1
BCC_A2 phase:al-se:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
FCC_A1 phase:al-se:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–944.34 K, x(Se) 0–0	3	1
HCP_A3 phase:al-se: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:al-se:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 494–2500 K, x(Se) 0–1	5	1

HEXAGONAL_A8 (Al–Se)

Id: phase:al-se:a8-hexagonal; status assigned
Structure: gamma-Se · A8 · hP3 · P3_121 (152); type st:a8-gamma-se-hp3; tier A: standard phase name; confidence high
Stoichiometry: Se 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–494 K, x(Se) 1–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:al-se:a8-hexagonal, corpus:phase:al-se:hexagonal-a8
paper: paper:10.1007/s11669-019-00733-z:(Se)
tdb: tdb:AlSe-19Shi.tdb:HEXAGONAL_A8

TDB models of HEXAGONAL_A8 (1): PHASE and CONSTITUENT statements as written

AlSe-19Shi.tdb: HEXAGONAL_A8, type code %, sha256 990a49c151cafe47…

52: PHASE HEXAGONAL_A8 % 1 1 !
53: CONST HEXAGONAL_A8 : SE : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase; reports values for this phase

AL2SE3 (Al–Se)

Id: phase:al-se:al2se3; status assigned
Structure: beta-Ga2Se3 · mC20 · Cc (9); type st:beta-ga2se3-mc20; 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 (mp_oqmd_space_groups_differ, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Al 0.4000, Se 0.6000
Stability: stable in 1 of 1 calculated diagram(s): 300–1207.32 K, x(Se) 0.6–0.6
Literature: 13 values (13 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-se:al2se3
paper: paper:10.1007/s11669-019-00733-z:Al2Se3
tdb: tdb:AlSe-19Shi.tdb:AL2SE3

TDB models of AL2SE3 (1): PHASE and CONSTITUENT statements as written

AlSe-19Shi.tdb: AL2SE3, type code %, sha256 990a49c151cafe47…

57: PHASE AL2SE3 % 2 2 3 !
58: CONST AL2SE3 : AL : SE : !

Example references (3 of 3; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase; reports values for this phase
doi:10.1107/s0365110x66001506 G. A. Steigmann, J. Goodyear, The crystal structure of Al<sub>2</sub>Se<sub>3</sub>, Acta Cryst 20, 617-619 (1966).
cited as the source of values for this phase
doi:10.1002/zaac.19542770107 A. Schneider, G. Gattow, Beitrag zum System Aluminium–Selen, Zeitschrift anorg allge chemie 277, 49-59 (1954).
cited as the source of values for this phase

BCC_A2 (Al–Se)

Id: phase:al-se:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stoichiometry: Al 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:al-se:bcc-a2
tdb: tdb:AlSe-19Shi.tdb:BCC_A2

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

AlSe-19Shi.tdb: BCC_A2, type code %B, sha256 990a49c151cafe47…

42: PHASE BCC_A2 %B 2 1 3 !
43: CONST BCC_A2 : AL : VA : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase

FCC_A1 (Al–Se)

Id: phase:al-se:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stoichiometry: Al 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–944.34 K, x(Se) 0–0
Literature: 3 values (3 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-se:fcc-a1
paper: paper:10.1007/s11669-019-00733-z:(αAl)
tdb: tdb:AlSe-19Shi.tdb:FCC_A1

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

AlSe-19Shi.tdb: FCC_A1, type code %A, sha256 990a49c151cafe47…

37: PHASE FCC_A1 %A 2 1 1 !
38: CONST FCC_A1 : AL : VA : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase; reports values for this phase

HCP_A3 (Al–Se)

Id: phase:al-se: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: Al 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:al-se:hcp-a3
tdb: tdb:AlSe-19Shi.tdb:HCP_A3

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

AlSe-19Shi.tdb: HCP_A3, type code %A, sha256 990a49c151cafe47…

47: PHASE HCP_A3 %A 2 1 0.5 !
48: CONST HCP_A3 : AL : VA: !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase

LIQUID (Al–Se)

Id: phase:al-se:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 494–2500 K, x(Se) 0–1
Literature: 5 values (5 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:al-se:liquid
paper: paper:10.1007/s11669-019-00733-z:L
tdb: tdb:AlSe-19Shi.tdb:LIQUID

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

AlSe-19Shi.tdb: LIQUID, type code %, sha256 990a49c151cafe47…

32: PHASE LIQUID % 1 1 !
33: CONST LIQUID : AL SE : !

Example references (1 of 1; assessments first):

doi:10.1007/s11669-019-00733-z Chenying Shi, Biaobiao Yang, Biao Hu, Yong Du, Sheng Yao, Thermodynamic Description of the Al–X (X = S, Se, Te) Systems, J. Phase Equilib. Diffus. 40, 392-402 (2019).
assessment that models this phase; 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}
}