N–V phases

5 phases (tier A 2, liquid 1, gas 1, interstitial_fcc_a1_compound 1); 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 · N–V system page · Markdown · field reference

Phases of the N–V system (5)
Phase	Structure	Basis	Stability (calculated)	TDB models
BCC_A2 phase:n-v:bcc-a2	W · A2 · cI2 · Im-3m (229)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–2198.52 K, x(N) 0–0.14936	2
FCC_A1 phase:n-v:fcc-a1	NaCl · B1 · cF8 · Fm-3m (225)	assigned	stable in 2 of 2 calculated diagram(s): 300–2393.43 K, x(N) 0.37866–0.5	2
HCP_A3 phase:n-v:hcp-a3	Mg · A3 · hP2 · P6_3/mmc (194)	tier A: standard phase name	stable in 2 of 2 calculated diagram(s): 300–2682.63 K, x(N) 0.24214–0.33333	2
LIQUID phase:n-v:liquid	liquid	liquid	stable in 2 of 2 calculated diagram(s): 2110–4000 K, x(N) 0–0.23338	2
N2GAS phase:n-v:n2gas	gas	gas	stable in 2 of 2 calculated diagram(s): 300–4000 K, x(N) 1–1	2

BCC_A2 (N–V)

Id: phase:n-v: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 2 of 2 calculated diagram(s): 300–2198.52 K, x(N) 0–0.14936
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:n-v:bcc-a2
tdb: tdb:VN-91Oht-LB.tdb:BCC_A2, tdb:VN-97Du.tdb:BCC_A2

TDB models of BCC_A2 (2): PHASE and CONSTITUENT statements as written

VN-91Oht-LB.tdb: BCC_A2, type code %B, sha256 2acab6ca1bd63897…

42: PHASE BCC_A2 %B 2 1 3 !
43: CONST BCC_A2 : V% : N VA% : !

VN-97Du.tdb: BCC_A2, type code %B, sha256 4add1267df6db927…

41: PHASE BCC_A2 %B 2 1 3 !
42: CONST BCC_A2 : V% : N VA% : !

Example references (2 of 2; assessments first):

doi:10.1016/0364-5916(91)90022-C H. Ohtani, M. Hillert, Calphad, 15, 11-24(1991).
assessment that models this phase
doi:10.3139/ijmr-1997-0101 Y. Du, R. Schmid-Fetzer, H. Ohtani, Z. Metallkd., 88, 545-56(1997).
assessment that models this phase

FCC_A1 (N–V)

Id: phase:n-v:fcc-a1; status assigned
Structure: NaCl · B1 · cF8 · Fm-3m (225); type st:b1-nacl-cf8; interstitial_fcc_a1_compound; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 300–2393.43 K, x(N) 0.37866–0.5
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:n-v:fcc-a1
tdb: tdb:VN-91Oht-LB.tdb:FCC_A1, tdb:VN-97Du.tdb:FCC_A1

TDB models of FCC_A1 (2): PHASE and CONSTITUENT statements as written

VN-91Oht-LB.tdb: FCC_A1, type code %A, sha256 2acab6ca1bd63897…

37: PHASE FCC_A1 %A 2 1 1 !
38: CONST FCC_A1 : V : N VA% : !

VN-97Du.tdb: FCC_A1, type code %A, sha256 4add1267df6db927…

36: PHASE FCC_A1 %A 2 1 1 !
37: CONST FCC_A1 : V : N VA% : !

Example references (2 of 2; assessments first):

doi:10.1016/0364-5916(91)90022-C H. Ohtani, M. Hillert, Calphad, 15, 11-24(1991).
assessment that models this phase
doi:10.3139/ijmr-1997-0101 Y. Du, R. Schmid-Fetzer, H. Ohtani, Z. Metallkd., 88, 545-56(1997).
assessment that models this phase

HCP_A3 (N–V)

Id: phase:n-v: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 2 of 2 calculated diagram(s): 300–2682.63 K, x(N) 0.24214–0.33333
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:n-v:hcp-a3
tdb: tdb:VN-91Oht-LB.tdb:HCP_A3, tdb:VN-97Du.tdb:HCP_A3

TDB models of HCP_A3 (2): PHASE and CONSTITUENT statements as written

VN-91Oht-LB.tdb: HCP_A3, type code %A, sha256 2acab6ca1bd63897…

47: PHASE HCP_A3 %A 2 1 0.5 !
48: CONST HCP_A3 : V : N VA% : !

VN-97Du.tdb: HCP_A3, type code %A, sha256 4add1267df6db927…

46: PHASE HCP_A3 %A 2 1 0.5 !
47: CONST HCP_A3 : V : N VA% : !

Example references (2 of 2; assessments first):

doi:10.1016/0364-5916(91)90022-C H. Ohtani, M. Hillert, Calphad, 15, 11-24(1991).
assessment that models this phase
doi:10.3139/ijmr-1997-0101 Y. Du, R. Schmid-Fetzer, H. Ohtani, Z. Metallkd., 88, 545-56(1997).
assessment that models this phase

LIQUID (N–V)

Id: phase:n-v:liquid; status assigned
Structure: liquid; type st:liquid; liquid; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 2110–4000 K, x(N) 0–0.23338
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:n-v:liquid
tdb: tdb:VN-91Oht-LB.tdb:LIQUID, tdb:VN-97Du.tdb:LIQUID

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

VN-91Oht-LB.tdb: LIQUID, type code %, sha256 2acab6ca1bd63897…

32: PHASE LIQUID:L % 1 1 !
33: CONST LIQUID:L : N V : !

VN-97Du.tdb: LIQUID, type code %, sha256 4add1267df6db927…

31: PHASE LIQUID:L % 1 1 !
32: CONST LIQUID:L : N V : !

Example references (2 of 2; assessments first):

doi:10.1016/0364-5916(91)90022-C H. Ohtani, M. Hillert, Calphad, 15, 11-24(1991).
assessment that models this phase
doi:10.3139/ijmr-1997-0101 Y. Du, R. Schmid-Fetzer, H. Ohtani, Z. Metallkd., 88, 545-56(1997).
assessment that models this phase

N2GAS (N–V)

Id: phase:n-v:n2gas; status assigned
Structure: gas; type st:gas; gas; confidence high
Stability: stable in 2 of 2 calculated diagram(s): 300–4000 K, x(N) 1–1
Literature: 0 values (0 accepted) from 0 papers
Interactive: phase registry entry

Names (3): corpus: corpus:phase:n-v:n2gas
tdb: tdb:VN-91Oht-LB.tdb:N2GAS, tdb:VN-97Du.tdb:N2GAS

TDB models of N2GAS (2): PHASE and CONSTITUENT statements as written

VN-91Oht-LB.tdb: N2GAS, type code %, sha256 2acab6ca1bd63897…

50: PHASE N2GAS % 1 1 !
51: CONST N2GAS : N2 : !

VN-97Du.tdb: N2GAS, type code %, sha256 4add1267df6db927…

49: PHASE N2GAS % 1 1 !
50: CONST N2GAS : N2 : !

Example references (2 of 2; assessments first):

doi:10.1016/0364-5916(91)90022-C H. Ohtani, M. Hillert, Calphad, 15, 11-24(1991).
assessment that models this phase
doi:10.3139/ijmr-1997-0101 Y. Du, R. Schmid-Fetzer, H. Ohtani, Z. Metallkd., 88, 545-56(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}
}