Co–Mo phases

8 phases (tier A 7, liquid 1); 8 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 · Co–Mo system page · Markdown · field reference

Phases of the Co–Mo system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:co-mo:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–3999.76 K, x(Mo) 0.92756–1	0	4
CO3MO_D019 phase:co-mo:co3mo-d019	Ni3Sn · D0_19 · hP8 · P6_3/mmc (194)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–1320.71 K, x(Mo) 0.25–0.25	0	4
MU_D85 phase:co-mo:d85-mu	Fe7W6 · D8_5 · hR13 · R-3m (166)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–1787.02 K, x(Mo) 0.40996–0.49553	4	4
SIGMA_D8B phase:co-mo:d8b-sigma	sigma-CrFe · D8_b · tP30 · P4_2/mnm (136)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 1270–1892.98 K, x(Mo) 0.62346–0.64346	4	2
FCC_A1 phase:co-mo:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 660.07–1767.99 K, x(Mo) 0–0.18678	0	4
HCP_A3 phase:co-mo:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 4 of 4 calculated diagram(s): 300–1474.4 K, x(Mo) 0–0.19681	0	4
LIQUID phase:co-mo:liquid	liquid	liquid	stable in 4 of 4 calculated diagram(s): 1608.27–4000 K, x(Mo) 0–1	0	4
SIGMA_OLD phase:co-mo:old-sigma	sigma-CrFe · D8_b · tP30 · P4_2/mnm (136)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 1230–1892.88 K, x(Mo) 0.6152–0.65039	0	2

BCC_A2 (Co–Mo)

Id: phase:co-mo:bcc-a2; status assigned
Structure: W · A2 · cI2 · Im-3m (229); type st:a2-w-ci2; tier A: standard phase name; confidence high
Stability: stable in 4 of 4 calculated diagram(s): 300–3999.76 K, x(Mo) 0.92756–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-mo:bcc-a2
tdb: tdb:CoMo-03Dav-LB.tdb:BCC_A2, tdb:CoMo-03Dav-alt.tdb:BCC_A2, tdb:CoMo-99Dav-alt.tdb:BCC_A2, tdb:CoMo-99Dav.tdb:BCC_A2

TDB models of BCC_A2 (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: BCC_A2, type code %B, sha256 a58bcde388de52ca…

36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : CO MO% : VA : !

CoMo-03Dav-alt.tdb: BCC_A2, type code %B, sha256 2d6edda32b27d420…

37: PHASE BCC_A2 %B 2 1 3 !
38: CONST BCC_A2 : CO MO% : VA : !

CoMo-99Dav-alt.tdb: BCC_A2, type code %B, sha256 d2c8829a651a1f9b…

36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : CO MO% : VA : !

CoMo-99Dav.tdb: BCC_A2, type code %B, sha256 7aa9e898710f4b97…

35: PHASE BCC_A2 %B 2 1 3 !
36: CONST BCC_A2 : CO MO% : VA : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase

CO3MO_D019 (Co–Mo)

Id: phase:co-mo:co3mo-d019; status assigned
Structure: Ni3Sn · D0_19 · hP8 · P6_3/mmc (194); type st:d0-19-ni3sn-hp8; tier A: standard phase name; confidence high
Caveat: DFT agrees: on-hull mp-aaaaabrv and oqmd-29399, space group 194
Stoichiometry: Co 0.7500, Mo 0.2500
Stability: stable in 4 of 4 calculated diagram(s): 300–1320.71 K, x(Mo) 0.25–0.25
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (7): corpus: corpus:phase:co-mo:co3mo-d019
mp: mp:mp-aaaaabrv
oqmd: oqmd:oqmd-29399
tdb: tdb:CoMo-03Dav-LB.tdb:CO3MO_D019, tdb:CoMo-03Dav-alt.tdb:CO3MO_D019, tdb:CoMo-99Dav-alt.tdb:CO3MO_D019, tdb:CoMo-99Dav.tdb:CO3MO_D019

TDB models of CO3MO_D019 (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: CO3MO_D019, type code %, sha256 a58bcde388de52ca…

46: PHASE CO3MO_D019 % 2 3 1  !
47: CONST CO3MO_D019 : CO : MO : !

CoMo-03Dav-alt.tdb: CO3MO_D019, type code %, sha256 2d6edda32b27d420…

47: PHASE CO3MO_D019 % 2 3 1  !
48: CONST CO3MO_D019 : CO : MO : !

CoMo-99Dav-alt.tdb: CO3MO_D019, type code %, sha256 d2c8829a651a1f9b…

46: PHASE CO3MO_D019 % 2 3 1  !
47: CONST CO3MO_D019 : CO : MO : !

CoMo-99Dav.tdb: CO3MO_D019, type code %, sha256 7aa9e898710f4b97…

45: PHASE CO3MO_D019 % 2 3 1  !
46: CONST CO3MO_D019 : CO : MO : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase

MU_D85 (Co–Mo)

Id: phase:co-mo:d85-mu; status assigned
Structure: Fe7W6 · D8_5 · hR13 · R-3m (166); type st:d8-5-fe7w6-hr13; tier A: standard phase name; confidence high
Caveat: partitioned order/disorder model in CoMo-03Dav-LB.tdb also describes the disordered state
Caveat: partitioned order/disorder model in CoMo-03Dav-alt.tdb also describes the disordered state
Caveat: partitioned order/disorder model in CoMo-99Dav-alt.tdb also describes the disordered state
Caveat: partitioned order/disorder model in CoMo-99Dav.tdb also describes the disordered state
Stability: stable in 4 of 4 calculated diagram(s): 300–1787.02 K, x(Mo) 0.40996–0.49553
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (7): corpus: corpus:phase:co-mo:d85-mu, corpus:phase:co-mo:mu-d85
paper: paper:10.1361/105497103770330505:μ
tdb: tdb:CoMo-03Dav-LB.tdb:MU_D85, tdb:CoMo-03Dav-alt.tdb:MU_D85, tdb:CoMo-99Dav-alt.tdb:MU_D85, tdb:CoMo-99Dav.tdb:MU_D85

TDB models of MU_D85 (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: MU_D85, type code %, sha256 a58bcde388de52ca…

51: PHASE MU_D85 % 4 1 4 2 6 !
52: CONST MU_D85 : CO MO : MO : CO MO : CO : !

CoMo-03Dav-alt.tdb: MU_D85, type code %, sha256 2d6edda32b27d420…

52: PHASE MU_D85 % 3 7 2 4 !
53: CONST MU_D85 : CO MO : MO : CO MO : !

CoMo-99Dav-alt.tdb: MU_D85, type code %, sha256 d2c8829a651a1f9b…

51: PHASE MU_D85 % 3 7 2 4 !
52: CONST MU_D85 : CO MO : MO : CO MO : !

CoMo-99Dav.tdb: MU_D85, type code %, sha256 7aa9e898710f4b97…

50: PHASE MU_D85 % 4 1 4 2 6 !
51: CONST MU_D85 : CO MO : MO : CO MO : CO : !

Example references (3 of 3; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase; reports values for this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase
doi:10.1007/bf02881194 Leo Brewer, R. H. Lamoreaux, R. Ferro, R. Marazza, The As-Mo system (Arsenic-Molybdenum), Bulletin of Alloy Phase Diagrams 1, 76-78 (1980).
cited as the source of values for this phase

SIGMA_D8B (Co–Mo)

Id: phase:co-mo:d8b-sigma; status assigned
Structure: sigma-CrFe · D8_b · tP30 · P4_2/mnm (136); type st:d8-b-sigma-crfe-tp30; tier A: standard phase name; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 1270–1892.98 K, x(Mo) 0.62346–0.64346
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-mo:d8b-sigma, corpus:phase:co-mo:sigma-d8b
paper: paper:10.1361/105497103770330505:σ
tdb: tdb:CoMo-03Dav-LB.tdb:SIGMA_D8B, tdb:CoMo-99Dav.tdb:SIGMA_D8B

TDB models of SIGMA_D8B (2): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: SIGMA_D8B, type code %, sha256 a58bcde388de52ca…

56: PHASE SIGMA_D8B % 3 10 4 16 !
57: CONST SIGMA_D8B : CO : MO : CO MO : !

CoMo-99Dav.tdb: SIGMA_D8B, type code %, sha256 7aa9e898710f4b97…

55: PHASE SIGMA_D8B % 3 10 4 16 !
56: CONST SIGMA_D8B : CO : MO : CO MO : !

Example references (3 of 3; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase; reports values for this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase
doi:10.1007/bf02881194 Leo Brewer, R. H. Lamoreaux, R. Ferro, R. Marazza, The As-Mo system (Arsenic-Molybdenum), Bulletin of Alloy Phase Diagrams 1, 76-78 (1980).
cited as the source of values for this phase

FCC_A1 (Co–Mo)

Id: phase:co-mo: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 4 of 4 calculated diagram(s): 660.07–1767.99 K, x(Mo) 0–0.18678
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-mo:fcc-a1
tdb: tdb:CoMo-03Dav-LB.tdb:FCC_A1, tdb:CoMo-03Dav-alt.tdb:FCC_A1, tdb:CoMo-99Dav-alt.tdb:FCC_A1, tdb:CoMo-99Dav.tdb:FCC_A1

TDB models of FCC_A1 (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: FCC_A1, type code %A, sha256 a58bcde388de52ca…

31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : CO% MO : VA : !

CoMo-03Dav-alt.tdb: FCC_A1, type code %A, sha256 2d6edda32b27d420…

32: PHASE FCC_A1 %A 2 1 1 !
33: CONST FCC_A1 : CO% MO : VA : !

CoMo-99Dav-alt.tdb: FCC_A1, type code %A, sha256 d2c8829a651a1f9b…

31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : CO% MO : VA : !

CoMo-99Dav.tdb: FCC_A1, type code %A, sha256 7aa9e898710f4b97…

30: PHASE FCC_A1 %A 2 1 1 !
31: CONST FCC_A1 : CO% MO : VA : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase

HCP_A3 (Co–Mo)

Id: phase:co-mo: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 4 of 4 calculated diagram(s): 300–1474.4 K, x(Mo) 0–0.19681
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-mo:hcp-a3
tdb: tdb:CoMo-03Dav-LB.tdb:HCP_A3, tdb:CoMo-03Dav-alt.tdb:HCP_A3, tdb:CoMo-99Dav-alt.tdb:HCP_A3, tdb:CoMo-99Dav.tdb:HCP_A3

TDB models of HCP_A3 (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: HCP_A3, type code %A, sha256 a58bcde388de52ca…

41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : CO% MO : VA : !

CoMo-03Dav-alt.tdb: HCP_A3, type code %A, sha256 2d6edda32b27d420…

42: PHASE HCP_A3 %A 2 1 0.5 !
43: CONST HCP_A3 : CO% MO : VA : !

CoMo-99Dav-alt.tdb: HCP_A3, type code %A, sha256 d2c8829a651a1f9b…

41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : CO% MO : VA : !

CoMo-99Dav.tdb: HCP_A3, type code %A, sha256 7aa9e898710f4b97…

40: PHASE HCP_A3 %A 2 1 0.5 !
41: CONST HCP_A3 : CO% MO : VA : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase

LIQUID (Co–Mo)

Id: phase:co-mo:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 4 of 4 calculated diagram(s): 1608.27–4000 K, x(Mo) 0–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:co-mo:liquid
tdb: tdb:CoMo-03Dav-LB.tdb:LIQUID, tdb:CoMo-03Dav-alt.tdb:LIQUID, tdb:CoMo-99Dav-alt.tdb:LIQUID, tdb:CoMo-99Dav.tdb:LIQUID

TDB models of LIQUID (4): PHASE and CONSTITUENT statements as written

CoMo-03Dav-LB.tdb: LIQUID, type code %, sha256 a58bcde388de52ca…

26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : CO MO : !

CoMo-03Dav-alt.tdb: LIQUID, type code %, sha256 2d6edda32b27d420…

27: PHASE LIQUID:L % 1 1 !
28: CONST LIQUID:L : CO MO : !

CoMo-99Dav-alt.tdb: LIQUID, type code %, sha256 d2c8829a651a1f9b…

26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : CO MO : !

CoMo-99Dav.tdb: LIQUID, type code %, sha256 7aa9e898710f4b97…

25: PHASE LIQUID:L % 1 1 !
26: CONST LIQUID:L : CO MO : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
assessment that models this phase

SIGMA_OLD (Co–Mo)

Id: phase:co-mo:old-sigma; status assigned
Structure: sigma-CrFe · D8_b · tP30 · P4_2/mnm (136); type st:d8-b-sigma-crfe-tp30; tier A: standard phase name; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 1230–1892.88 K, x(Mo) 0.6152–0.65039
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:co-mo:old-sigma
tdb: tdb:CoMo-03Dav-alt.tdb:SIGMA_OLD, tdb:CoMo-99Dav-alt.tdb:SIGMA_OLD

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

CoMo-03Dav-alt.tdb: SIGMA_OLD, type code %, sha256 2d6edda32b27d420…

57: PHASE SIGMA_OLD % 3 8 4 18 !
58: CONST SIGMA_OLD : CO : MO : CO MO : !

CoMo-99Dav-alt.tdb: SIGMA_OLD, type code %, sha256 d2c8829a651a1f9b…

56: PHASE SIGMA_OLD % 3 8 4 18 !
57: CONST SIGMA_OLD : CO : MO : CO MO : !

Example references (2 of 2; assessments first):

doi:10.1361/105497103770330505 A. V. Davydov, U. R. Kattner, Revised thermodynamic description for the Co-Mo system, JPE 24, 209-211 (2003).
assessment that models this phase
doi:10.1361/105497199770335893 A. Davydov, U. R. Kattner, Thermodynamic assessment of the Co-Mo system, JPE 20, 5-16 (1999).
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}
}