C–La phases

9 phases (tier A 7, tier C 1, 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 · C–La system page · Markdown · field reference

Phases of the C–La system (9)
Phase	Structure	Basis	Stability (calculated)	TDB models
DIAMOND_A4 phase:c-la:a4-diamond	C (diamond) · A4 · cF8 · Fd-3m (227)	tier A: standard phase name	not stable in 1 calculated diagram(s)	1
GRAPHITE_A9 phase:c-la:a9-graphite	C (graphite) · A9 · hP4 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1	1
BCC_A2 phase:c-la:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 1134–1201.72 K, x(C) 0–0.02557	1
DHCP phase:c-la:dhcp-a3	alpha-La · A3' · hP4 · P6_3/mmc (194)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1164.99 K, x(C) 0–0	1
FCC_A1 phase:c-la:fcc-a1	Cu · A1 · cF4 · Fm-3m (225)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 540.47–1164.99 K, x(C) 0–0.04346	1
LA2C3_D5C phase:c-la:la2c3-d5c	Pu2C3 · D5_c · cI40 · I-43d (220)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1690.25 K, x(C) 0.57834–0.6	1
LAC2_BETA phase:c-la:lac2-beta	CaC2 · cF36 · Fm-3m (225)	tier C: assessor-stated (Hallstedt 2025 crystallographic table)	stable in 1 of 1 calculated diagram(s): 1366.41–2631.23 K, x(C) 0.64636–0.66352	1
LAC2_C11A phase:c-la:lac2-c11a	CaC2 · C11_a · tI6 · I4/mmm (139)	tier A: standard phase name	stable in 1 of 1 calculated diagram(s): 300–1365.22 K, x(C) 0.66667–0.66667	1
LIQUID phase:c-la:liquid	liquid	liquid	stable in 1 of 1 calculated diagram(s): 1080.88–4000 K, x(C) 0–0.8563	1

DIAMOND_A4 (C–La)

Id: phase:c-la:a4-diamond; status assigned
Structure: C (diamond) · A4 · cF8 · Fd-3m (227); type st:a4-c-diamond-cf8; tier A: standard phase name; confidence high
Stoichiometry: C 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:c-la:a4-diamond
tdb: tdb:LaC-11Pen.tdb:DIAMOND_A4

TDB models of DIAMOND_A4 (1): PHASE and CONSTITUENT statements as written

LaC-11Pen.tdb: DIAMOND_A4, type code %, sha256 15a0d1b7ceb20373…

53: PHASE DIAMOND_A4 % 1 1 !
54: CONST DIAMOND_A4 : C : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

GRAPHITE_A9 (C–La)

Id: phase:c-la:a9-graphite; status assigned
Structure: C (graphite) · A9 · hP4 · P6_3/mmc (194); type st:a9-c-graphite-hp4; tier A: standard phase name; confidence high
Stoichiometry: C 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–4000 K, x(C) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:a9-graphite
tdb: tdb:LaC-11Pen.tdb:GRAPHITE_A9

TDB models of GRAPHITE_A9 (1): PHASE and CONSTITUENT statements as written

LaC-11Pen.tdb: GRAPHITE_A9, type code %, sha256 15a0d1b7ceb20373…

58: PHASE GRAPHITE_A9 % 1 1 !
59: CONST GRAPHITE_A9 : C : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

BCC_A2 (C–La)

Id: phase:c-la: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): 1134–1201.72 K, x(C) 0–0.02557
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:bcc-a2
tdb: tdb:LaC-11Pen.tdb:BCC_A2

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

LaC-11Pen.tdb: BCC_A2, type code %B, sha256 15a0d1b7ceb20373…

43: PHASE BCC_A2 %B 2 1 3 !
44: CONST BCC_A2 : LA : C VA% : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

DHCP (C–La)

Id: phase:c-la:dhcp-a3; status assigned
Structure: alpha-La · A3' · hP4 · P6_3/mmc (194); type st:a3-alpha-la-hp4; tier A: standard phase name; confidence high
Stoichiometry: La 1.0000
Stability: stable in 1 of 1 calculated diagram(s): 300–1164.99 K, x(C) 0–0
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:dhcp-a3
tdb: tdb:LaC-11Pen.tdb:DHCP

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

LaC-11Pen.tdb: DHCP, type code %, sha256 15a0d1b7ceb20373…

48: PHASE DHCP % 1 1 !
49: CONST DHCP : LA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

FCC_A1 (C–La)

Id: phase:c-la: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): 540.47–1164.99 K, x(C) 0–0.04346
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:fcc-a1
tdb: tdb:LaC-11Pen.tdb:FCC_A1

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

LaC-11Pen.tdb: FCC_A1, type code %A, sha256 15a0d1b7ceb20373…

38: PHASE FCC_A1 %A 2 1 1 !
39: CONST FCC_A1 : LA : C VA% : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

LA2C3_D5C (C–La)

Id: phase:c-la:la2c3-d5c; status assigned
Structure: Pu2C3 · D5_c · cI40 · I-43d (220); type st:d5-c-pu2c3-ci40; tier A: standard phase name; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 300–1690.25 K, x(C) 0.57834–0.6
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:la2c3-d5c
tdb: tdb:LaC-11Pen.tdb:LA2C3_D5C

TDB models of LA2C3_D5C (1): PHASE and CONSTITUENT statements as written

LaC-11Pen.tdb: LA2C3_D5C, type code %, sha256 15a0d1b7ceb20373…

63: PHASE LA2C3_D5C % 2 2 3 !
64: CONST LA2C3_D5C : LA : C% VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

LAC2_BETA (C–La)

Id: phase:c-la:lac2-beta; status assigned
Structure: CaC2 · cF36 · Fm-3m (225); type st:cac2-cf36; 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_structure_token, off_stoichiometric_model); structure as stated in the SGTE crystallographic table for this phase name and system
Stability: stable in 1 of 1 calculated diagram(s): 1366.41–2631.23 K, x(C) 0.64636–0.66352
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:lac2-beta
tdb: tdb:LaC-11Pen.tdb:LAC2_BETA

TDB models of LAC2_BETA (1): PHASE and CONSTITUENT statements as written

LaC-11Pen.tdb: LAC2_BETA, type code %, sha256 15a0d1b7ceb20373…

73: PHASE LAC2_BETA % 2 1 2 !
74: CONST LAC2_BETA : LA : C% VA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

LAC2_C11A (C–La)

Id: phase:c-la:lac2-c11a; status assigned
Structure: CaC2 · C11_a · tI6 · I4/mmm (139); type st:c11-a-cac2-ti6; tier A: standard phase name; confidence high
Stoichiometry: C 0.6667, La 0.3333
Stability: stable in 1 of 1 calculated diagram(s): 300–1365.22 K, x(C) 0.66667–0.66667
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:lac2-c11a
tdb: tdb:LaC-11Pen.tdb:LAC2_C11A

TDB models of LAC2_C11A (1): PHASE and CONSTITUENT statements as written

LaC-11Pen.tdb: LAC2_C11A, type code %, sha256 15a0d1b7ceb20373…

68: PHASE LAC2_C11A % 2 1 2 !
69: CONST LAC2_C11A : LA : C : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
assessment that models this phase

LIQUID (C–La)

Id: phase:c-la:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 1 of 1 calculated diagram(s): 1080.88–4000 K, x(C) 0–0.8563
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (2): corpus: corpus:phase:c-la:liquid
tdb: tdb:LaC-11Pen.tdb:LIQUID

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

LaC-11Pen.tdb: LIQUID, type code %, sha256 15a0d1b7ceb20373…

33: PHASE LIQUID:L % 1 1 !
34: CONST LIQUID:L : C LA : !

Example references (1 of 1; assessments first):

doi:10.1016/j.calphad.2011.09.002 Yingbiao Peng, Yong Du, Lijun Zhang, Chunsheng Sha, Shuhong Liu, Feng Zheng et al., Thermodynamic modeling of the C–RE (RE=La, Ce and Pr) systems, Calphad 35, 533-541 (2011).
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}
}