AlP: enthalpy of formation

28 accepted literature formation-enthalpy value(s) (experimental 12, model 15, unspecified 1); experimental median -32.135 kJ/mol-atom (n = 4); Materials Project -58.834 kJ/mol-atom (mp-aaaaachq); OQMD -71.088 kJ/mol-atom (oqmd-4641).

Systems: Al–P

Literature values

Enthalpy of formation of AlP reported in the literature (28)
Value	Phase as printed	T (K)	Class	Method	System	Source	Location
-90.2 kJ/mol (basis unstated)	AlP	298.15	experimental		Al–P	[1] Miettinen 2015 cites Peviak 1974	Table 4, p. 6, row 8 report
-90.2 per mol-atom ± 4	AlP	298.15	experimental	Measured	Al–P	[2] Liang 2013 cites Peviak 1974	Table 3, p. 3, row 4 report
-82.6 per mol-atom ± 1	AlP	298.15	experimental	Measured	Al–P	[2] Liang 2013 cites Kischio 1965 doi	Table 3, p. 3, row 2 report
-82.6 kJ/mol (basis unstated)	AlP	298.15	experimental		Al–P	[1] Miettinen 2015 cites Kischio 1965 doi	Table 4, p. 6, row 6 report
-81.6 per mol-atom ± 1	AlP	298.15	experimental	Measured	Al–P	[2] Liang 2013 cites Martosudirdjo 1974 doi	Table 3, p. 3, row 3 report
-81.6 kJ/mol (basis unstated)	AlP	298.15	experimental		Al–P	[1] Miettinen 2015 cites Martosudirdjo 1974 doi	Table 4, p. 6, row 7 report
-69.4 per mol-atom ± 4	AlP	298.15	experimental	Measured	Al–P	[2] Liang 2013 cites Wang 1963 doi	Table 3, p. 3, row 1 report
-69.4 kJ/mol (basis unstated)	AlP	298.15	experimental		Al–P	[1] Miettinen 2015 cites Wang 1963 doi	Table 4, p. 6, row 5 report
-41.3 kJ/mol-atom ± 0.55	AlP	298.15	experimental		Al–P	[3] Tu 2009 cites Kischio 1965 doi	Table 3, p. 4, row 2 report
-34.77 kJ/mol-atom ± 2.3	AlP	298.15	experimental		Al–P	[3] Tu 2009 cites Wang 1963 doi	Table 3, p. 4, row 1 report
-29.5 kJ/mol-atom ± 3.35	AlP	298.15	experimental		Al–P	[3] Tu 2009 cites G 1968	Table 3, p. 4, row 3 report
-28.8 kJ/mol-atom ± 8.85	AlP	298.15	experimental		Al–P	[3] Tu 2009 cites Martosudirdjo 1974 doi	Table 3, p. 4, row 4 report
-164.5 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[4] Onderka 2002 cites Kaufman 1981	Table AI, p. 19, row 8 report
-148.6 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[4] Onderka 2002 cites Ansara 1994	Table AI, p. 19, row 6 report
-91.5 per mol-atom	AlP	298.15	model	Calculated	Al–P	[2] Liang 2013 cites Kaufman 1981 doi	Table 3, p. 3, row 5 report
-82.2 per mol-atom	AlP	298.15	model	Reviewed	Al–P	[2] Liang 2013 cites Barin 1977	Table 3, p. 3, row 12 report
-82.2 per mol-atom	AlP	298.15	model	Calculated	Al–P	[2] Liang 2013 cites Wu 2012 doi	Table 3, p. 3, row 9 report
-81.8 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[1] Miettinen 2015	Table 4, p. 6, row 4 report
-81.6 per mol-atom	AlP	298.15	model	Calphad	Al–P	[2] Liang 2013	Table 3, p. 3, row 14 report
-81.6 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[1] Miettinen 2015 cites Liang 2013 doi	Table 4, p. 6, row 3 report
-80.4 per mol-atom	AlP	298.15	model	Calculated	Al–P	[2] Liang 2013 cites McAlister 2013	Table 3, p. 3, row 6 report
-74.3 per mol-atom	AlP	298.15	model	Calculated	Al–P	[2] Liang 2013 cites Ansara 1994 doi	Table 3, p. 3, row 7 report
-74.3 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[1] Miettinen 2015 cites Ansara 1994 doi	Table 4, p. 6, row 1 report
-67.7 per mol-atom ± 6.7	AlP	298.15	model	Derived	Al–P	[2] Liang 2013 cites De 1968	Table 3, p. 3, row 13 report
-51 kJ/mol (basis unstated)	AlP	298.15	model		Al–P	[1] Miettinen 2015 cites Tu 2009 doi	Table 4, p. 6, row 2 report
-51 per mol-atom	AlP	298.15	model	Calculated	Al–P	[2] Liang 2013 cites Tu 2009 doi	Table 3, p. 3, row 8 report
-25.5 kJ/mol-atom	AlP	298.15	model		Al–P	[3] Tu 2009	Table 3, p. 4, row 5 report
-166.5 kJ/mol (basis unstated)	AlP	298.15	unspecified		Al–P	[4] Onderka 2002 cites Wagman 1968	Table AI, p. 19, row 7 report

Uncertainty budget

Components kept separate, in the value's unit (literature SCHEMA.md, UNCERTAINTY_CALIBRATION.md): effective = max(sqrt(max(printed, reading, method)^2 + composition^2 + conversion^2), scatter). The method floor is the robust between-study scatter of the method class in ORCHID (calibrated) or a documented prior; printed values and printed uncertainties are unchanged.

Uncertainty budget of the literature values of AlP
Value	Unit	Printed	Reading	Method (class, basis)	Effective
-90.2	kJ/mol (basis unstated)		0.05	7 (unknown, calibrated)	7
-90.2	per mol-atom	4	0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	4
-82.6	per mol-atom	1	0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	1
-82.6	kJ/mol (basis unstated)		0.05	7 (unknown, calibrated)	7
-81.6	per mol-atom	1	0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	1
-81.6	kJ/mol (basis unstated)		0.05	7 (unknown, calibrated)	7
-69.4	per mol-atom	4	0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	4
-69.4	kJ/mol (basis unstated)		0.05	7 (unknown, calibrated)	7
-41.3	kJ/mol-atom	0.55	2.500e-4	3.5 (unknown, calibrated)	3.5
-34.77	kJ/mol-atom	2.3	2.500e-4	3.5 (unknown, calibrated)	3.5
-29.5	kJ/mol-atom	3.35	2.500e-4	3.5 (unknown, calibrated)	3.5
-28.8	kJ/mol-atom	8.85	2.500e-4	3.5 (unknown, calibrated)	8.85
-164.5	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-148.6	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-91.5	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-82.2	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-82.2	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-81.8	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-81.6	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-81.6	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-80.4	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-74.3	per mol-atom		0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-74.3	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-67.7	per mol-atom	6.7	0.05	unit 'per mol-atom' not convertible to kJ/mol-atom	6.7
-51	kJ/mol (basis unstated)		0.05	7.8 (model_calculated, calibrated)	7.8
-51	per mol-atom		0.5	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-25.5	kJ/mol-atom		2.500e-4	3.9 (model_calculated, calibrated)	3.9
-166.5	kJ/mol (basis unstated)		0.05	7 (unknown, calibrated)	7

DFT formation energies

Lowest-energy entries at this composition. Materials Project and OQMD use different energy references and are never averaged. 1 eV/atom = 96.485 kJ/mol-atom.

DFT formation energy of AlP
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaaachq	-58.834	-0.609772	F-43m	0	0	no
OQMD	oqmd-4641	-71.088	-0.736775	F-43m	0	0	no

DFT sources: A. Jain et al., Commentary: The Materials Project: A materials genome approach to accelerating materials innovation, APL Materials 1 (2013) 011002. doi:10.1063/1.4812323 (CC BY 4.0); J. E. Saal et al., JOM 65 (2013) 1501-1509; S. Kirklin et al., npj Comput. Mater. 1 (2015) 15010. doi:10.1007/s11837-013-0755-4 (CC BY 4.0);

Sources

Jyrki Miettinen, Seppo Louhenkilpi, Gueorgui Vassilev, Thermodynamic Description of Ternary Fe-X-P Systems. Part 9: Fe-Al-P, J. Phase Equilib. Diffus. 36, 317-326 (2015). doi:10.1007/s11669-015-0383-5
Song-Mao Liang, Rainer Schmid-Fetzer, Thermodynamic assessment of the Al–P system based on original experimental data, Calphad 42, 76-85 (2013). doi:10.1016/j.calphad.2013.07.001
Hao Tu, Fucheng Yin, Xuping Su, Ya Liu, Xinming Wang, Experimental investigation and thermodynamic modeling of the Al–P–Zn ternary system, Calphad 33, 755-760 (2009). doi:10.1016/j.calphad.2009.10.003
B. Onderka, J. Unland, R. Schmid-Fetzer, Thermodynamics and phase stability in the In–N system, J. Mater. Res. 17, 3065-3083 (2002). doi:10.1557/jmr.2002.0445

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-Parity: DFT-vs-experiment formation-enthalpy benchmark (version 2026.10; Version 1, machine-extracted), Zenodo (2026). doi:10.5281/zenodo.23735943
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); 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); G. Kim, S. V. Meschel, P. Nash, W. Chen, Experimental formation enthalpies for intermetallic phases and other inorganic compounds, Scientific Data 4 (2017) 170162, https://doi.org/10.1038/sdata.2017.162; 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. 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_dft_benchmark_2026,
  author    = {Arr{\'o}yave, Raymundo and Saal, James and Shin, Dongwon},
  title     = {{ORCHID-Parity: DFT-vs-experiment formation-enthalpy benchmark}},
  version   = {2026.10},
  publisher = {Zenodo},
  year      = {2026},
  doi       = {10.5281/zenodo.23735943},
  url       = {https://doi.org/10.5281/zenodo.23735943},
  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}
}