Ag–S phases

9 phases (tier A 4, liquid 1, needs_review 4); 6 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 · Ag–S system page · Markdown · field reference

Phases of the Ag–S system (9)
Phase	Structure	Basis	Stability (calculated)	TDB models
ORTHORHOMBIC_A16 phase:ag-s:a16-orthorhombic	alpha-S · A16 · oF128 · Fddd (70)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–385.34 K, x(S) 1–1	1
AG2S_ALPHA phase:ag-s:ag2s-alpha		needs_review	stable in 1 of 1 calculated diagram(s): 300–450.75 K, x(S) 0.33333–0.33333	1
AG2S_BETA phase:ag-s:ag2s-beta		needs_review	stable in 1 of 1 calculated diagram(s): 441.92–897.41 K, x(S) 0.33333–0.33551	1
AG2S_GAMMA phase:ag-s:ag2s-gamma		needs_review	stable in 1 of 1 calculated diagram(s): 851.43–1099.34 K, x(S) 0.33333–0.33333	1
BCC_A2 phase:ag-s:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
FCC_A1 phase:ag-s:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1234.93 K, x(S) 0–0	1
HCP_A3 phase:ag-s:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
LIQUID phase:ag-s:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 384.29–2500 K, x(S) 0–1	1
MONOCLINIC_S phase:ag-s:s-monoclinic		needs_review	not stable in 1 calculated diagram(s)	1

ORTHORHOMBIC_A16 (Ag–S)

Id: phase:ag-s:a16-orthorhombic; status assigned
Structure: alpha-S · A16 · oF128 · Fddd (70); type st:a16-alpha-s-of128; tier A: standard phase name; confidence high
Stoichiometry: S 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–385.34 K, x(S) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:a16-orthorhombic
tdb: tdb:AgS-18Shi.tdb:ORTHORHOMBIC_A16

TDB models of ORTHORHOMBIC_A16 (1): PHASE and CONSTITUENT statements as written

AgS-18Shi.tdb: ORTHORHOMBIC_A16, type code %, sha256 88ca76a77dda3d77…

49: PHASE ORTHORHOMBIC_A16 % 1 1 !
50: CONST ORTHORHOMBIC_A16 : S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

AG2S_ALPHA (Ag–S)

Id: phase:ag-s:ag2s-alpha; status needs_review
No structure assigned. Why: mp_oqmd_space_groups_differ; no_structure_token
Candidate (dft_mp): P2_1/m (11) — on-hull MP Ag2S at x(S)=0.3333
Candidate (dft_oqmd): Pnma (62) — on-hull OQMD Ag2 S1 at x(S)=0.3333
Candidate (sgte_mmc2): Ag2S-alpha · mP12 · P2_1/c (14) — Hallstedt 2025 mmc2 row for AG2S_ALPHA: Ag2S-alpha
Candidate (tdb_comment): Ag2S-alpha · mP12 · P2_1/c — AgS-18Shi.tdb: 'Prototype Ag2S-alpha (mP12, P2_1/c)'
Stoichiometry: Ag 0.6667, S 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–450.75 K, x(S) 0.33333–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:ag2s-alpha
tdb: tdb:AgS-18Shi.tdb:AG2S_ALPHA

TDB models of AG2S_ALPHA (1): PHASE and CONSTITUENT statements as written

AgS-18Shi.tdb: AG2S_ALPHA, type code %, sha256 88ca76a77dda3d77…

59: PHASE AG2S_ALPHA % 2 2 1 !
60: CONST AG2S_ALPHA : AG : S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

AG2S_BETA (Ag–S)

Id: phase:ag-s:ag2s-beta; status needs_review
No structure assigned. Why: no_structure_token; off_stoichiometric_model
Candidate (dft_mp): P2_1/m (11) — on-hull MP Ag2S at x(S)=0.3333
Candidate (dft_oqmd): Pnma (62) — on-hull OQMD Ag2 S1 at x(S)=0.3333
Candidate (sgte_mmc2): Ag2S-beta · cI20 · Im-3m (229) — Hallstedt 2025 mmc2 row for AG2S_BETA: Ag2S-beta
Candidate (tdb_comment): Ag2S-beta · cI20 · Im-3m — AgS-18Shi.tdb: 'Prototype Ag2S-beta (cI20, Im-3m)'
Stability: stable in 1 of 1 calculated diagram(s): 441.92–897.41 K, x(S) 0.33333–0.33551
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:ag2s-beta
tdb: tdb:AgS-18Shi.tdb:AG2S_BETA

TDB models of AG2S_BETA (1): PHASE and CONSTITUENT statements as written

AgS-18Shi.tdb: AG2S_BETA, type code %, sha256 88ca76a77dda3d77…

64: PHASE AG2S_BETA % 2 2 1 !
65: CONST AG2S_BETA : AG% S : S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

AG2S_GAMMA (Ag–S)

Id: phase:ag-s:ag2s-gamma; status needs_review
No structure assigned. Why: no_structure_token; off_stoichiometric_model
Candidate (sgte_mmc2): Cu2Se-beta · cF44 · Fm-3m (225) — Hallstedt 2025 mmc2 row for AG2S_GAMMA: Ag2S-gamma
Candidate (tdb_comment): Cu2Se-beta · cF44 · Fm-3m — AgS-18Shi.tdb: 'Prototype Cu2Se-beta (cF44, Fm-3m)'
Stability: stable in 1 of 1 calculated diagram(s): 851.43–1099.34 K, x(S) 0.33333–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:ag2s-gamma
tdb: tdb:AgS-18Shi.tdb:AG2S_GAMMA

TDB models of AG2S_GAMMA (1): PHASE and CONSTITUENT statements as written

AgS-18Shi.tdb: AG2S_GAMMA, type code %, sha256 88ca76a77dda3d77…

69: PHASE AG2S_GAMMA % 2 2 1 !
70: CONST AG2S_GAMMA : AG% S : S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

BCC_A2 (Ag–S)

Id: phase:ag-s:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stoichiometry: Ag 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:ag-s:bcc-a2
tdb: tdb:AgS-18Shi.tdb:BCC_A2

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

AgS-18Shi.tdb: BCC_A2, type code %B, sha256 88ca76a77dda3d77…

39: PHASE BCC_A2 %B 2 1 3 !
40: CONST BCC_A2 : AG : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

FCC_A1 (Ag–S)

Id: phase:ag-s:fcc-a1; status assigned
Structure: Cu · A1 · cF4 · Fm-3m (225); type st:a1-cu-cf4; tier A: standard phase name; confidence high
Stoichiometry: Ag 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–1234.93 K, x(S) 0–0
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:fcc-a1
tdb: tdb:AgS-18Shi.tdb:FCC_A1

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

AgS-18Shi.tdb: FCC_A1, type code %A, sha256 88ca76a77dda3d77…

34: PHASE FCC_A1 %A 2 1 1 !
35: CONST FCC_A1 : AG : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

HCP_A3 (Ag–S)

Id: phase:ag-s: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: Ag 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:ag-s:hcp-a3
tdb: tdb:AgS-18Shi.tdb:HCP_A3

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

AgS-18Shi.tdb: HCP_A3, type code %A, sha256 88ca76a77dda3d77…

44: PHASE HCP_A3 %A 2 1 0.5 !
45: CONST HCP_A3 : AG : VA: !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

LIQUID (Ag–S)

Id: phase:ag-s:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 384.29–2500 K, x(S) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-s:liquid
tdb: tdb:AgS-18Shi.tdb:LIQUID

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

AgS-18Shi.tdb: LIQUID, type code %, sha256 88ca76a77dda3d77…

29: PHASE LIQUID:L % 1 1 !
30: CONST LIQUID:L : AG AG2S S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
assessment that models this phase

MONOCLINIC_S (Ag–S)

Id: phase:ag-s:s-monoclinic; status needs_review
No structure assigned. Why: name_has_descriptive_tokens:MONOCLINIC; no_structure_token
Candidate (sgte_mmc2): beta-S · mP48 · P2_1/c (14) — Hallstedt 2025 mmc2 row for MONOCLINIC_S: beta-S
Candidate (tdb_comment): beta-S · mP48 · P2_1/a — AgS-18Shi.tdb: 'Prototype beta-S (mP48, P2_1/a)'
Stoichiometry: S 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:ag-s:s-monoclinic
tdb: tdb:AgS-18Shi.tdb:MONOCLINIC_S

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

AgS-18Shi.tdb: MONOCLINIC_S, type code %, sha256 88ca76a77dda3d77…

54: PHASE MONOCLINIC_S % 1 1 !
55: CONST MONOCLINIC_S : S : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2018.07.004 C. Shi, Y. Du, B. Hu, B. Yang, Y. Pan, F. Guo, S. Liu, Q. Du, Calphad, 62, 207-14(2018).
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}
}