Nb–P system

36 accepted literature values from 1 paper(s) (experimental 17, model 19); 1 calculated phase diagram(s).

Data: JSON · CSV · interactive explorer · interactive phase diagram · phases (10) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	17
model	19

Accepted values by property group
Property group	Values
crystal structure	36

Calculated phase diagrams

Binary phase diagrams calculated with pycalphad 0.11.2 from the SGTE binary collection (Hallstedt 2025, CC BY 4.0). Evidence class: model.

Assessments with a calculated phase diagram
TDB file	Assessment	SHA-256	Links
NbP-09Tok.tdb	T. Tokunaga, N. Hanaya, H. Ohtani, M. Hasebe, ISIJ Int., 49, 947-56(2009). doi:10.2355/isijinternational.49.947	`ce209315ccfc4ebbba01ab3bda83198bdc32028e231907e43b5144b19bcad11d`	viewer · TDB · JSON

Calculated three-phase invariants (model, mole fraction of the second component)
TDB file	T (K)	Phases at the invariant
NbP-09Tok.tdb	1733.63	LIQUID (x(P) 0.33855) + NB7P4 (x(P) 0.36364) + NBP (x(P) 0.5)
NbP-09Tok.tdb	1733.63	LIQUID (x(P) 0.33878) + NB7P4 (x(P) 0.36364) + NBP (x(P) 0.5)
NbP-09Tok.tdb	1733.63	LIQUID (x(P) 0.33852) + NB7P4 (x(P) 0.36364) + NBP (x(P) 0.5)
NbP-09Tok.tdb	1603.57	BCC_A2 (x(P) 0.06253) + LIQUID (x(P) 0.23714) + NB7P4 (x(P) 0.36364)
NbP-09Tok.tdb	1603.57	BCC_A2 (x(P) 0.0625) + LIQUID (x(P) 0.23711) + NB7P4 (x(P) 0.36364)
NbP-09Tok.tdb	1302.59	NBP (x(P) 0.5) + NBP2 (x(P) 0.66667) + LIQUID (x(P) 0.72273)
NbP-09Tok.tdb	1302.59	NBP (x(P) 0.5) + NBP2 (x(P) 0.66667) + LIQUID (x(P) 0.72271)
NbP-09Tok.tdb	573.75	BCC_A2 (x(P) 0) + NB3P (x(P) 0.25) + NB7P4 (x(P) 0.36364)
NbP-09Tok.tdb	519	NBP2 (x(P) 0.66667) + LIQUID (x(P) 0.88512) + RED_P (x(P) 1)
NbP-09Tok.tdb	519	NBP2 (x(P) 0.66667) + LIQUID (x(P) 0.88513) + RED_P (x(P) 1)
NbP-09Tok.tdb	519	NBP2 (x(P) 0.66667) + LIQUID (x(P) 0.88513) + RED_P (x(P) 1)

Convex hulls: Materials Project DFT hull · OQMD DFT hull

Other properties

Crystal structure (36)

Crystal structure, Nb–P system
Property	Value	Phases / composition	Class	Source	Location
Lattice a	6.621 Å	Nb2P in (Fe,Nb)2P	model	[1] Tokunaga 2009	Table 1, p. 4, row 3 report
Lattice a	10.128 Å	Nb3P alloy: Nb 0.75, P 0.25	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 2 report
Lattice a	9.986 Å	Nb3P alloy: Nb 0.75, P 0.25	model	[1] Tokunaga 2009	Table 1, p. 4, row 1 report
Lattice a	25.384 Å	Nb5P3 alloy: Nb 0.625, P 0.375	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 8 report
Lattice a	25.167 Å	Nb5P3 alloy: Nb 0.625, P 0.375	model	[1] Tokunaga 2009	Table 1, p. 4, row 7 report
Lattice a	15.023 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	model	[1] Tokunaga 2009	Table 1, p. 4, row 5 report
Lattice a	14.95 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 6 report
Lattice a	25.975 Å	Nb8P5 alloy: Nb 0.615385, P 0.384615	model	[1] Tokunaga 2009	Table 1, p. 4, row 9 report
Lattice a	26.2 Å	Nb8P5 alloy: Nb 0.615385, P 0.384615	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 10 report
Lattice a	3.334 Å	NbP alloy: Nb 0.5, P 0.5	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 12 report
Lattice a	3.438 Å	NbP alloy: Nb 0.5, P 0.5	model	[1] Tokunaga 2009	Table 1, p. 4, row 11 report
Lattice a	6.461 Å	NbP2 alloy: Nb 0.333333, P 0.666667	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 14 report
Lattice a	6.351 Å	NbP2 alloy: Nb 0.333333, P 0.666667	model	[1] Tokunaga 2009	Table 1, p. 4, row 13 report
Lattice b	3.433 Å	Nb5P3 alloy: Nb 0.625, P 0.375	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 8 report
Lattice b	3.404 Å	Nb5P3 alloy: Nb 0.625, P 0.375	model	[1] Tokunaga 2009	Table 1, p. 4, row 7 report
Lattice b	17.691 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	model	[1] Tokunaga 2009	Table 1, p. 4, row 5 report
Lattice b	17.605 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 6 report
Lattice b	9.465 Å	Nb8P5 alloy: Nb 0.615385, P 0.384615	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 10 report
Lattice b	7.887 Å	NbP2 alloy: Nb 0.333333, P 0.666667	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 14 report
Lattice b	7.753 Å	NbP2 alloy: Nb 0.333333, P 0.666667	model	[1] Tokunaga 2009	Table 1, p. 4, row 13 report
Lattice c	3.902 Å	Nb2P in (Fe,Nb)2P	model	[1] Tokunaga 2009	Table 1, p. 4, row 3 report
Lattice c	5.089 Å	Nb3P alloy: Nb 0.75, P 0.25	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 2 report
Lattice c	5.017 Å	Nb3P alloy: Nb 0.75, P 0.25	model	[1] Tokunaga 2009	Table 1, p. 4, row 1 report
Lattice c	11.483 Å	Nb5P3 alloy: Nb 0.625, P 0.375	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 8 report
Lattice c	11.385 Å	Nb5P3 alloy: Nb 0.625, P 0.375	model	[1] Tokunaga 2009	Table 1, p. 4, row 7 report
Lattice c	3.457 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	model	[1] Tokunaga 2009	Table 1, p. 4, row 5 report
Lattice c	3.499 Å	Nb7P4 alloy: Nb 0.636364, P 0.363636	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 6 report
Lattice c	3.434 Å	Nb8P5 alloy: Nb 0.615385, P 0.384615	model	[1] Tokunaga 2009	Table 1, p. 4, row 9 report
Lattice c	3.464 Å	Nb8P5 alloy: Nb 0.615385, P 0.384615	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 10 report
Lattice c	11.378 Å	NbP alloy: Nb 0.5, P 0.5	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 12 report
Lattice c	11.767 Å	NbP alloy: Nb 0.5, P 0.5	model	[1] Tokunaga 2009	Table 1, p. 4, row 11 report
Lattice c	3.84 Å	NbP2 alloy: Nb 0.333333, P 0.666667	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 14 report
Lattice c	3.775 Å	NbP2 alloy: Nb 0.333333, P 0.666667	model	[1] Tokunaga 2009	Table 1, p. 4, row 13 report
lattice gamma	120 °	Nb2P in (Fe,Nb)2P	model	[1] Tokunaga 2009	Table 1, p. 4, row 3 report
lattice gamma	130.5 °	Nb7P4 alloy: Nb 0.636364, P 0.363636	model	[1] Tokunaga 2009	Table 1, p. 4, row 5 report
lattice gamma	130.5 °	Nb7P4 alloy: Nb 0.636364, P 0.363636	experimental	[1] Tokunaga 2009	Table 1, p. 4, row 6 report

Sources

Reporting papers the values were read from (a value cited from another work names that work in its row).

Tatsuya Tokunaga, Naoko Hanaya, Hiroshi Ohtani, Mitsuhiro Hasebe, Thermodynamic Analysis of Phase Equilibria in the Fe–Nb–P Ternary System, ISIJ Int. 49, 947-956 (2009). doi:10.2355/isijinternational.49.947

Please cite

R. Arróyave, J. Saal, D. Shin, ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735569
R. Arróyave, J. Saal, D. Shin, ORCHID-Diagrams: calculated binary phase diagrams (version 2026.10), Zenodo (2026). doi:10.5281/zenodo.23735859
R. Arróyave, J. Saal, D. Shin, ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD) (version 2026.10), Zenodo (2026). doi:10.5281/zenodo.23735891
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 the original source of every value you use (paper_citation / paper_doi, and cited_dois for values the paper cites from earlier work); 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). 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_literature_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Values: thermodynamic and phase-equilibrium values read from the literature}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735569},
  url       = {https://doi.org/10.5281/zenodo.23735569},
  note      = {Version 1, machine-extracted}
}

@misc{orchid_phase_diagrams_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Diagrams: calculated binary phase diagrams}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735859},
  url       = {https://doi.org/10.5281/zenodo.23735859}
}

@misc{orchid_hulls_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Hulls: binary convex hulls (Materials Project, OQMD, assessed CALPHAD)}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735891},
  url       = {https://doi.org/10.5281/zenodo.23735891}
}

@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}
}