Ag–O phases

8 phases (tier A 3, tier C 1, liquid 2, gas 2); 5 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–O system page · Markdown · field reference

Phases of the Ag–O system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:ag-o:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
CUPRITE_C3 phase:ag-o:c3-cuprite	Cu2O · C3 · cP6 · Pn-3m (224)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–301 K, x(O) 0.33333–0.33333	8	1
FCC_A1 phase:ag-o:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1235.08 K, x(O) 0–0.00057	0	1
GAS phase:ag-o:gas	gas	gas	stable in 1 of 1 calculated diagram(s): 300–2432.39 K, x(O) 0–1	0	1
HCP_A3 phase:ag-o:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	not stable in 1 calculated diagram(s)	0	1
ION phase:ag-o:ion	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1211.42–2432.39 K, x(O) 0–0.02078	0	1
LIQUID phase:ag-o:liquid	liquid	liquid	not stable in 1 calculated diagram(s)	1	1
O2GAS phase:ag-o:o2gas	gas	gas	stable in 1 of 1 calculated diagram(s): 466.46–1036.46 K, x(O) 1–1	0	1

BCC_A2 (Ag–O)

Id: phase:ag-o: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 1 calculated diagram(s)
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-o:bcc-a2
tdb: tdb:AgO-97Ass-LB.tdb:BCC_A2

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

AgO-97Ass-LB.tdb: BCC_A2, type code %B, sha256 9f608fb28b4b4e31…

49: PHASE BCC_A2 %B 2 1 3 !
50: CONST BCC_A2 : AG : VA% O : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase

CUPRITE_C3 (Ag–O)

Id: phase:ag-o:c3-cuprite; status assigned
Structure: Cu2O · C3 · cP6 · Pn-3m (224); type st:c3-cu2o-cp6; 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 (unrecognised_name_tokens:CUPRITE); structure as stated in the SGTE crystallographic table for this phase name and system
Stability: stable in 1 of 1 calculated diagram(s): 300–301 K, x(O) 0.33333–0.33333
Literature: 8 values (8 accepted) from 1 papers
Interactive: phase registry entry

Names (4): corpus: corpus:phase:ag-o:c3-cuprite, corpus:phase:ag-o:cuprite-c3
paper: paper:10.1111/j.1151-2916.1997.tb03232.x:Ag2O
tdb: tdb:AgO-97Ass-LB.tdb:CUPRITE_C3

TDB models of CUPRITE_C3 (1): PHASE and CONSTITUENT statements as written

AgO-97Ass-LB.tdb: CUPRITE_C3, type code %, sha256 9f608fb28b4b4e31…

59: PHASE CUPRITE_C3:I % 2 2 1 !
60: CONST CUPRITE_C3:I : AG+1 : O-2 : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase; reports values for this phase

FCC_A1 (Ag–O)

Id: phase:ag-o: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 1 of 1 calculated diagram(s): 300–1235.08 K, x(O) 0–0.00057
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-o:fcc-a1
tdb: tdb:AgO-97Ass-LB.tdb:FCC_A1

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

AgO-97Ass-LB.tdb: FCC_A1, type code %A, sha256 9f608fb28b4b4e31…

44: PHASE FCC_A1 %A 2 1 1 !
45: CONST FCC_A1 : AG : VA% O : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase

GAS (Ag–O)

Id: phase:ag-o:gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–2432.39 K, x(O) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-o:gas
tdb: tdb:AgO-97Ass-LB.tdb:GAS

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

AgO-97Ass-LB.tdb: GAS, type code %, sha256 9f608fb28b4b4e31…

65: PHASE GAS:G % 1 1 !
66: CONST GAS:G : AG AG2 AGO O O2 O3 : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase

HCP_A3 (Ag–O)

Id: phase:ag-o: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: 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-o:hcp-a3
tdb: tdb:AgO-97Ass-LB.tdb:HCP_A3

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

AgO-97Ass-LB.tdb: HCP_A3, type code %A, sha256 9f608fb28b4b4e31…

54: PHASE HCP_A3 %A 2 1 0.5 !
55: CONST HCP_A3 : AG : VA% O : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase

ION (Ag–O)

Id: phase:ag-o:ion; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1211.42–2432.39 K, x(O) 0–0.02078
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-o:ion
tdb: tdb:AgO-97Ass-LB.tdb:ION

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

AgO-97Ass-LB.tdb: ION, type code %, sha256 9f608fb28b4b4e31…

39: PHASE ION:Y % 2 1 1 !
40: CONST ION:Y : AG+1 : O-2 VA : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase

LIQUID (Ag–O)

Id: phase:ag-o:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stoichiometry: Ag 1.0000
Stability: not stable in 1 calculated diagram(s)
Literature: 1 values (1 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ag-o:liquid
paper: paper:10.1111/j.1151-2916.1997.tb03232.x:L
tdb: tdb:AgO-97Ass-LB.tdb:LIQUID

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

AgO-97Ass-LB.tdb: LIQUID, type code %, sha256 9f608fb28b4b4e31…

36: PHASE LIQUID:L % 1 1 !
37: CONST LIQUID:L : AG : !

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
assessment that models this phase; reports values for this phase

O2GAS (Ag–O)

Id: phase:ag-o:o2gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 466.46–1036.46 K, x(O) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:ag-o:o2gas
tdb: tdb:AgO-97Ass-LB.tdb:O2GAS

TDB models of O2GAS (1): PHASE and CONSTITUENT statements as written

AgO-97Ass-LB.tdb: O2GAS, type code %, sha256 9f608fb28b4b4e31…

62: PHASE O2GAS % 1 1 !
63: CONST O2GAS : O2 :!

Example references (1 of 1; assessments first):

doi:10.1111/j.1151-2916.1997.tb03232.x Jérôme Assal, Bengt Hallstedt, Ludwig J. Gauckler, Thermodynamic Assessment of the Silver–Oxygen System, Journal of the American Ceramic Society 80, 3054-3060 (1997).
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}
}