NiTi: enthalpy of formation

43 accepted literature formation-enthalpy value(s) (experimental 10, model 17, DFT 16); experimental median -33.9 kJ/mol-atom (n = 5); Materials Project -38.194 kJ/mol-atom (mp-aaaaaboi); OQMD -40.284 kJ/mol-atom (oqmd-107703).

Systems: Ni–Ti

Literature values

Enthalpy of formation of NiTi reported in the literature (43)
Value	Phase as printed	T (K)	Class	Method	System	Source	Location
-34.2 per mol-atom ± 2000	NiTi	999.15	experimental		Ni–Ti	[1] Santhy 2015 cites Gomozov 1986	Table 9, p. 6, row 17 report
-34.15 kJ/mol-atom	NiTi(B2)	999	experimental	Calorimetry	Ni–Ti	[2] Hu 2014 cites Gomozov 1986	Table 1, p. 5, row 5 report
-34 kJ/mol-atom	NiTi(B2)	1460	experimental	Calorimetry	Ni–Ti	[2] Hu 2014 cites Gachon 1981 doi	Table 1, p. 5, row 3 report
-34 per mol-atom ± 2000	NiTi	1460.15	experimental		Ni–Ti	[1] Santhy 2015 cites Gachon 1981 doi	Table 9, p. 6, row 15 report
-33.911 per mol-atom ± 2000	NiTi	298.15	experimental		Ni–Ti	[1] Santhy 2015 cites Kubaschewski 1956 doi	Table 9, p. 6, row 13 report
-33.9 kJ/mol-atom	NiTi(B2)	298.15	experimental	Calorimetry	Ni–Ti	[2] Hu 2014 cites Kubaschewski 1956 doi	Table 1, p. 5, row 4 report
-33.9 kJ/mol-atom	TiNi-B2	298.15	experimental	direct synthesis calorimetry	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Kubaschewski 1958 doi	Table 6, p. 8, row 24 report
-33.1 per mol-atom ± 1100	NiTi	1477.15	experimental		Ni–Ti	[1] Santhy 2015 cites ref. 1998Guo	Table 9, p. 6, row 21 report
-33.1 kJ/mol-atom ± 1.1	NiTi(B2)	298.15	experimental		Ni–Ti	[4] Tokunaga 2004 cites Guo 1998 doi	Table 2, p. 3, row 3 report
-32.51 per mol-atom	NiTi	1173.15	experimental		Ni–Ti	[1] Santhy 2015 cites Yi 1989 doi	Table 9, p. 6, row 19 report
-46 kJ/mol-atom	NiTi(B2)		model	TBB	Ni–Ti	[2] Hu 2014 cites Colinet 1993 doi	Table 1, p. 5, row 1 report
-45.8 per mol-atom	NiTi	298.15	model	Miedema	Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 28 report
-38.347 per mol-atom	NiTi	1477.15	model		Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 22 report
-38.286 per mol-atom	NiTi	1460.15	model		Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 16 report
-38.1 per mol-atom	NiTi		model	FP	Ni–Ti	[1] Santhy 2015 cites Pasturel 1995 doi	Table 9, p. 6, row 25 report
-37.721 kJ/mol-atom	TiNi B19'	298.15	model	Calphad assessment	Ni–Ti	[3] Povoden-Karadeniz 2013	Table 6, p. 8, row 33 report
-37.212 per mol-atom	NiTi	1173.15	model		Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 20 report
-36.5 kJ/mol-atom	NiTi(B32)		model	TBB	Ni–Ti	[2] Hu 2014 cites Colinet 1993 doi	Table 1, p. 5, row 8 report
-36.1 per mol-atom	NiTi		model	FP	Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 27 report
-36 per mol-atom	NiTi		model	FP	Ni–Ti	[1] Santhy 2015 cites Pasturel 1995 doi	Table 9, p. 6, row 26 report
-34.721 kJ/mol-atom	TiNi-B2	298.15	model	Calphad assessment	Ni–Ti	[3] Povoden-Karadeniz 2013	Table 6, p. 8, row 21 report
-34.16 per mol-atom	NiTi	999.15	model		Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 18 report
-34.052 kJ/mol-atom	TiNi-B2	298.15	model	Calphad assessment	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Bellen 1996	Table 6, p. 8, row 22 report
-33.85 kJ/mol-atom	NiTi(B2)	298.15	model	CALPHAD	Ni–Ti	[2] Hu 2014	Table 1, p. 5, row 7 report
-33.339 kJ/mol-atom	TiNi-B2	298.15	model	Calphad assessment	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Matsumoto 2005 doi	Table 6, p. 8, row 23 report
-31.159 per mol-atom	NiTi	298.15	model		Ni–Ti	[1] Santhy 2015	Table 9, p. 6, row 14 report
-9.8 kJ/mol-atom	NiTi(B32)	298.15	model	CALPHAD	Ni–Ti	[2] Hu 2014	Table 1, p. 5, row 11 report
-40.9 kJ/mol-atom	NiTi(B2)		DFT	LMTO	Ni–Ti	[2] Hu 2014 cites Colinet 1993 doi	Table 1, p. 5, row 2 report
-39.8 kJ/mol-atom	TiNi B19'	0	DFT	1st-princ. (LMTO-ASA)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Pasturel 1995 doi	Table 6, p. 8, row 35 report
-39.5 kJ/mol-atom	TiNi B19'	0	DFT	1st-princ. (FLAPW)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Hatcher 2009 doi	Table 6, p. 8, row 37 report
-38.5 kJ/mol-atom	NiTi(B32)		DFT	LMTO	Ni–Ti	[2] Hu 2014 cites Colinet 1993 doi	Table 1, p. 5, row 9 report
-38.1 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (LMTO-ASA)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Pasturel 1995 doi	Table 6, p. 8, row 26 report
-38 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (FP-LMTO)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Sanati 1998 doi	Table 6, p. 8, row 28 report
-37.8 kJ/mol-atom	TiNi B19'	0	DFT	1st-princ. (FP-LMTO)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Pasturel 1995 doi	Table 6, p. 8, row 36 report
-36.665 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (EMTO/GGA)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Lu 2007 doi	Table 6, p. 8, row 31 report
-36 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (FP-LMTO)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Pasturel 1995 doi	Table 6, p. 8, row 27 report
-34.59 kJ/mol-atom	NiTi(B2)	0	DFT	Ab initio	Ni–Ti	[4] Tokunaga 2004	Table 2, p. 3, row 2 report
-34.1 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (FLAPW)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Hatcher 2009 doi	Table 6, p. 8, row 29 report
-33.77 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (PW/LDA)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Huang 2002	Table 6, p. 8, row 32 report
-33.24 kJ/mol-atom	NiTi(B2)	0	DFT	First-principles	Ni–Ti	[2] Hu 2014	Table 1, p. 5, row 6 report
-32.784 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ., GGA	Ni–Ti	[3] Povoden-Karadeniz 2013	Table 6, p. 8, row 25 report
-31.84 kJ/mol-atom	TiNi-B2	0	DFT	1st-princ. (PW/PBE)	Ni–Ti	[3] Povoden-Karadeniz 2013 cites Stott 2010 doi	Table 6, p. 8, row 30 report
-29.29 kJ/mol-atom	NiTi(B32)	0	DFT	First-principles	Ni–Ti	[2] Hu 2014	Table 1, p. 5, row 10 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 NiTi
Value	Unit	Printed	Reading	Method (class, basis)	Effective
-34.2	per mol-atom	2000	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	2000
-34.15	kJ/mol-atom		0.005	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-34	kJ/mol-atom		0.5	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-34	per mol-atom	2000	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	2000
-33.911	per mol-atom	2000	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	2000
-33.9	kJ/mol-atom		0.05	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-33.9	kJ/mol-atom		5.000e-4	3.2 (solution_reaction_calorimetry, calibrated)	3.2
-33.1	per mol-atom	1100	5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	1100
-33.1	kJ/mol-atom	1.1	0.05	3.5 (unknown, calibrated)	3.5
-32.51	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-46	kJ/mol-atom		0.5	3.9 (model_calculated, calibrated)	3.9
-45.8	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-38.347	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-38.286	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-38.1	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-37.721	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-37.212	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-36.5	kJ/mol-atom		0.05	3.9 (model_calculated, calibrated)	3.9
-36.1	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-36	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-34.721	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-34.16	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-34.052	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-33.85	kJ/mol-atom		0.005	3.9 (model_calculated, calibrated)	3.9
-33.339	kJ/mol-atom		5.000e-4	3.9 (model_calculated, calibrated)	3.9
-31.159	per mol-atom		5.000e-4	unit 'per mol-atom' not convertible to kJ/mol-atom	unit 'per mol-atom' not convertible to kJ/mol-atom
-9.8	kJ/mol-atom		0.05	3.9 (model_calculated, calibrated)	3.9
-40.9	kJ/mol-atom		0.05	3.929 (dft, calibrated)	3.929
-39.8	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-39.5	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-38.5	kJ/mol-atom		0.05	3.929 (dft, calibrated)	3.929
-38.1	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-38	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-37.8	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-36.665	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-36	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-34.59	kJ/mol-atom		0.005	3.929 (dft, calibrated)	3.929
-34.1	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-33.77	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-33.24	kJ/mol-atom		0.005	3.929 (dft, calibrated)	3.929
-32.784	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-31.84	kJ/mol-atom		5.000e-4	3.929 (dft, calibrated)	3.929
-29.29	kJ/mol-atom		0.005	3.929 (dft, calibrated)	3.929

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 NiTi
Source	Entry	kJ/mol-atom	eV/atom	Space group	E above hull (kJ/mol-atom)	E above hull (eV/atom)	Theoretical
Materials Project	mp-aaaaaavz	-33.515	-0.347361	Pm-3m	4.679	0.0485	no
Materials Project	mp-aaaaaboi	-38.194	-0.395855	P2_1/m	0	0	no
OQMD	oqmd-107703	-40.284	-0.417516	P21/m	0.5977	0.0062	no
OQMD	oqmd-116608	-36.473	-0.378019	Pm-3m	4.4085	0.0457	no
OQMD	oqmd-2082617	-32.491	-0.336744	Fd-3m	8.391	0.087	yes

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

K. Santhy, K.C. Hari Kumar, Thermodynamic reassessment of Nb-Ni-Ti system with order–disorder model, Journal of Alloys and Compounds 619, 733-747 (2015). doi:10.1016/j.jallcom.2014.08.200
Biao Hu, Yong Du, J.C. Schuster, Weihua Sun, Shuhong Liu, Chengying Tang, Thermodynamic modeling of the Cr–Ni–Ti system using a four-sublattice model for ordered/disordered bcc phases, Thermochimica Acta 578, 35-42 (2014). doi:10.1016/j.tca.2014.01.002
E. Povoden-Karadeniz, D.C. Cirstea, P. Lang, T. Wojcik, E. Kozeschnik, Thermodynamics of Ti–Ni shape memory alloys, Calphad 41, 128-139 (2013). doi:10.1016/j.calphad.2013.02.004
Tatsuya Tokunaga, Koji Hashima, Hiroshi Ohtani, Mitsuhiro Hasebe, Thermodynamic Analysis of the Ni-Si-Ti System Using Thermochemical Properties Determined from Ab Initio Calculations, Mater. Trans. 45, 1507-1514 (2004). doi:10.2320/matertrans.45.1507

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}
}