Ca–Ni phases

8 phases (tier A 5, tier B 1, tier C 1, liquid 1); 7 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 · Ca–Ni system page · Markdown · field reference

Phases of the Ca–Ni system (8)
Phase	Structure	Basis	Stability (calculated)	Literature values	TDB models
BCC_A2 phase:ca-ni:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 716.15–1124.6 K, x(Ni) 0–0.00017	2	1
CA2NI7 phase:ca-ni:ca2ni7	Co7Gd2 · hR18 · R-3m (166)	tier B: DFT-supported (unique MP + OQMD match)	stable in 1 of 1 calculated diagram(s): 300–1376.06 K, x(Ni) 0.77778–0.77778	4	1
CANI2_C15 phase:ca-ni:cani2-c15	Cu2Mg · C15 · cF24 · Fd-3m (227)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1119.79 K, x(Ni) 0.66667–0.66667	7	1
CANI3 phase:ca-ni:cani3	Ni3Pu · hR12 · R-3m (166)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 300–1252.09 K, x(Ni) 0.75–0.75	4	1
CANI5_D2D phase:ca-ni:cani5-d2d	CaCu5 · D2_d · hP6 · P6/mmm (191)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1461.99 K, x(Ni) 0.83333–0.83333	6	1
FCC_A1 phase:ca-ni:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–2499.19 K, x(Ni) 0–1	2	1
HCP_A3 phase:ca-ni: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:ca-ni:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 899.6–2500 K, x(Ni) 0–1	12	1

BCC_A2 (Ca–Ni)

Id: phase:ca-ni: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 1 of 1 calculated diagram(s): 716.15–1124.6 K, x(Ni) 0–0.00017
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:bcc-a2
paper: paper:10.1016/j.calphad.2005.08.006:Ca-bcc
tdb: tdb:CaNi-05Isl.tdb:BCC_A2

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

CaNi-05Isl.tdb: BCC_A2, type code %B, sha256 d411c40b677aa318…

36: PHASE BCC_A2 %B 2 1 3 !
37: CONST BCC_A2 : CA% NI : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

CA2NI7 (Ca–Ni)

Id: phase:ca-ni:ca2ni7; status assigned
Structure: Co7Gd2 · hR18 · R-3m (166); type st:co7gd2-hr18; tier B: DFT-supported (unique MP + OQMD match); confidence high
Stoichiometry: Ca 0.2222, Ni 0.7778
Stability: stable in 1 of 1 calculated diagram(s): 300–1376.06 K, x(Ni) 0.77778–0.77778
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (5): corpus: corpus:phase:ca-ni:ca2ni7
mp: mp:mp-aaackycj
oqmd: oqmd:oqmd-2026083
paper: paper:10.1016/j.calphad.2005.08.006:Ca2Ni7
tdb: tdb:CaNi-05Isl.tdb:CA2NI7

TDB models of CA2NI7 (1): PHASE and CONSTITUENT statements as written

CaNi-05Isl.tdb: CA2NI7, type code %, sha256 d411c40b677aa318…

56: PHASE CA2NI7 % 2 2 7 !
57: CONST CA2NI7 : CA : NI : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

CANI2_C15 (Ca–Ni)

Id: phase:ca-ni:cani2-c15; status assigned
Structure: Cu2Mg · C15 · cF24 · Fd-3m (227); type st:c15-cu2mg-cf24; tier A: standard phase name; confidence high
Stoichiometry: Ca 0.3333, Ni 0.6667
Stability: stable in 1 of 1 calculated diagram(s): 300–1119.79 K, x(Ni) 0.66667–0.66667
Literature: 7 values (7 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:cani2-c15
paper: paper:10.1016/j.calphad.2005.08.006:CaNi2
tdb: tdb:CaNi-05Isl.tdb:CANI2_C15

TDB models of CANI2_C15 (1): PHASE and CONSTITUENT statements as written

CaNi-05Isl.tdb: CANI2_C15, type code %, sha256 d411c40b677aa318…

46: PHASE CANI2_C15 % 2 1 2 !
47: CONST CANI2_C15 : CA : NI : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

CANI3 (Ca–Ni)

Id: phase:ca-ni:cani3; status assigned
Structure: Ni3Pu · hR12 · R-3m (166); type st:ni3pu-hr12; 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_mp, no_structure_token); structure as stated in the SGTE crystallographic table for this phase name and system
Stoichiometry: Ca 0.2500, Ni 0.7500
Stability: stable in 1 of 1 calculated diagram(s): 300–1252.09 K, x(Ni) 0.75–0.75
Literature: 4 values (4 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:cani3
paper: paper:10.1016/j.calphad.2005.08.006:CaNi3
tdb: tdb:CaNi-05Isl.tdb:CANI3

TDB models of CANI3 (1): PHASE and CONSTITUENT statements as written

CaNi-05Isl.tdb: CANI3, type code %, sha256 d411c40b677aa318…

51: PHASE CANI3 % 2 1 3 !
52: CONST CANI3 : CA : NI : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

CANI5_D2D (Ca–Ni)

Id: phase:ca-ni:cani5-d2d; status assigned
Structure: CaCu5 · D2_d · hP6 · P6/mmm (191); type st:d2-d-cacu5-hp6; tier A: standard phase name; confidence high
Stoichiometry: Ca 0.1667, Ni 0.8333
Stability: stable in 1 of 1 calculated diagram(s): 300–1461.99 K, x(Ni) 0.83333–0.83333
Literature: 6 values (6 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:cani5-d2d
paper: paper:10.1016/j.calphad.2005.08.006:CaNi5
tdb: tdb:CaNi-05Isl.tdb:CANI5_D2D

TDB models of CANI5_D2D (1): PHASE and CONSTITUENT statements as written

CaNi-05Isl.tdb: CANI5_D2D, type code %, sha256 d411c40b677aa318…

61: PHASE CANI5_D2D % 2 1 5 !
62: CONST CANI5_D2D : CA : NI : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

FCC_A1 (Ca–Ni)

Id: phase:ca-ni: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): 300–2499.19 K, x(Ni) 0–1
Literature: 2 values (2 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:fcc-a1
paper: paper:10.1016/j.calphad.2005.08.006:Ni-fcc
tdb: tdb:CaNi-05Isl.tdb:FCC_A1

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

CaNi-05Isl.tdb: FCC_A1, type code %A, sha256 d411c40b677aa318…

31: PHASE FCC_A1 %A 2 1 1 !
32: CONST FCC_A1 : CA% NI% : VA : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of values for this phase

HCP_A3 (Ca–Ni)

Id: phase:ca-ni: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:ca-ni:hcp-a3
tdb: tdb:CaNi-05Isl.tdb:HCP_A3

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

CaNi-05Isl.tdb: HCP_A3, type code %A, sha256 d411c40b677aa318…

41: PHASE HCP_A3 %A 2 1 0.5 !
42: CONST HCP_A3 : CA NI : VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase

LIQUID (Ca–Ni)

Id: phase:ca-ni:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 899.6–2500 K, x(Ni) 0–1
Literature: 12 values (12 accepted) from 1 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:ca-ni:liquid
paper: paper:10.1016/j.calphad.2005.08.006:L
tdb: tdb:CaNi-05Isl.tdb:LIQUID

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

CaNi-05Isl.tdb: LIQUID, type code %, sha256 d411c40b677aa318…

26: PHASE LIQUID:L % 1 1 !
27: CONST LIQUID:L : CA NI : !

Example references (2 of 2; assessments first):

doi:10.1016/j.calphad.2005.08.006 F. Islam, M. Medraj, The phase equilibria in the Mg–Ni–Ca system, Calphad 29, 289-302 (2005).
assessment that models this phase; reports values for this phase
doi:10.1016/0022-5088(90)90338-k M. Notin, D. Belbacha, M. Rahmane, J. Hertz, G. Saindrenan, J.L. Jorda, Experimental diagram and numerical optimization of the CaNi system, Journal of the Less Common Metals 162, 221-229 (1990).
cited as the source of 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}
}