K–Na system

21 accepted literature values from 1 paper(s) (experimental 16, DFT 5); 2 calculated phase diagram(s). 2 further extracted value(s) not accepted by the reader-agreement checks are only in the JSON/CSV.

Data: JSON · CSV · interactive explorer · interactive phase diagram · phases (5) · papers (bibliography) · Markdown

Accepted values by evidence class
Evidence class	Values
experimental	16
DFT	5

Accepted values by property group
Property group	Values
invariant reaction	15
formation	2
crystal structure	4

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
KNa-06Zha.tdb	S. Zhang, C. Brubaker, C. Jiang, M. Yang, Y. Zhong, Q. Han, Z.-K. Liu, Mater. Sci. Eng. A, 418, 161-71(2006). doi:10.1016/j.msea.2005.11.037	`07051d7fbcc606b0b9f40e790d043042346a94fd71ab62c633b8bf4db2e417d7`	viewer · TDB · JSON
KNa-11Ren.tdb	X. Ren, C. Li, Z. Du, C. Guo, Calphad, 35, 446-54(2011). doi:10.1016/j.calphad.2011.06.005	`25965ca4d96d0c6da67d8929e4ea3152c9c806135e72d8e634a4686986f7ee61`	viewer · TDB · JSON

Convex hulls: Materials Project DFT hull · OQMD DFT hull · CALPHAD hull KNa-06Zha

Invariant reactions (literature)

Invariant reactions reported in the literature for the K–Na system (15)
T (K)	Reaction / phases	Compositions (mole fraction)	Class	Source	Location
280.5	Liquid = bcc (Na) + KNa2	Liquid: Na 0.6; bcc (Na): Na 0.97; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites MacDonald 1956 doi	Table 6, p. 9, row 7 report
280.07	Liquid = bcc (Na) + KNa2	Liquid: Na 0.598; bcc (Na): Na 0.992; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites Ott 1969 doi	Table 6, p. 9, row 6 report
280.058	Liquid = bcc (Na) + KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites Krier 1957 doi	Table 6, p. 9, row 8 report
280.053	Liquid = bcc (Na) + KNa2	Liquid: Na 0.593; bcc (Na): Na 0.993; KNa2: Na 0.667	DFT	[1] Zhang 2006	Table 6, p. 9, row 1 report
280.05	Liquid = bcc (Na) + KNa2	Liquid: Na 0.58; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites G 1912	Table 6, p. 9, row 3 report
280.05	Liquid = bcc (Na) + KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites Janecke 1928	Table 6, p. 9, row 4 report
280.03	Liquid = bcc (Na) + KNa2	Liquid: Na 0.5995; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites Kurnakow 1902 doi	Table 6, p. 9, row 2 report
279.75	Liquid = bcc (Na) + KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites Rinck 1933	Table 6, p. 9, row 5 report
261.17	Liquid + bcc (K) = KNa2	Liquid: Na 0.3033; bcc (K): Na 0.043; KNa2: Na 0.667	DFT	[1] Zhang 2006	Table 6, p. 9, row 9 report
261	Liquid + bcc (K) = KNa2	Liquid: Na 0.334; bcc (K): Na 0.045; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites MacDonald 1956 doi	Table 6, p. 9, row 14 report
260.65	Liquid + bcc (K) = KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites Rinck 1933	Table 6, p. 9, row 12 report
260.65	Liquid + bcc (K) = KNa2	Liquid: Na 0.3336; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites Kurnakow 1902 doi	Table 6, p. 9, row 10 report
260.55	Liquid + bcc (K) = KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites G 1912	Table 6, p. 9, row 11 report
260.53	Liquid + bcc (K) = KNa2	Liquid: Na 0.319; bcc (K): Na 0.046; KNa2: Na 0.667	experimental	[1] Zhang 2006 cites Ott 1969 doi	Table 6, p. 9, row 13 report
260.51	Liquid + bcc (K) = KNa2	KNa2: K 0.333333, Na 0.666667	experimental	[1] Zhang 2006 cites Krier 1957 doi	Table 6, p. 9, row 15 report

Formation enthalpies

Literature values in kJ/mol-atom where the per-atom basis is known. DFT columns: the lowest-energy entry at the same composition (Materials Project 2026.04.13, OQMD v1.8; different energy references, never averaged), from dft_parity.json.

Enthalpies of formation, K–Na system (2)
Phase	Compound	Value	T (K)	Class	MP DFT (kJ/mol-atom)	OQMD DFT (kJ/mol-atom)	Source	Location	Quote
KNa2		-0.699 kJ/mol-atom	0	DFT			[1] Zhang 2006	Table 2, p. 3, row 30 report
KNa2	KNa2	-0.60668 kJ/mol-atom	298.15	experimental	0.954 (mp-aaabgmji)	-7.272 (oqmd-668086)	[1] Zhang 2006 cites Hultgren 1963	Table 2, p. 3, row 31 report

Other properties

Crystal structure (4)

Crystal structure, K–Na system
Property	Value	T (K)	Phases / composition	Class	Source	Location
Lattice a printed: Lattice constant a	7.394 Å	0	KNa2 alloy: Na 0.667	DFT	[1] Zhang 2006	Table 2, p. 3, row 30 report
Lattice a printed: Lattice constant a	7.5 Å		KNa2 alloy: Na 0.667	experimental	[1] Zhang 2006 cites Laves 1943	Table 2, p. 3, row 14 report
Lattice c printed: Lattice constant c	12.083 Å	0	KNa2 alloy: Na 0.667	DFT	[1] Zhang 2006	Table 2, p. 3, row 30 report
Lattice c printed: Lattice constant c	12.31 Å		KNa2 alloy: Na 0.667	experimental	[1] Zhang 2006 cites Laves 1943	Table 2, p. 3, row 14 report

Sources

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

Shengjun Zhang, Carl Brubaker, Chao Jiang, Mei Yang, Yu Zhong, Qingyou Han et al., A combined first-principles calculation and thermodynamic modeling of the F–K–Na system, Materials Science and Engineering: A 418, 161-171 (2006). doi:10.1016/j.msea.2005.11.037

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}
}