Ammonia

• Formula: H₃N
• Molecular weight: 17.0305
• IUPAC Standard InChI: InChI=1S/H3N/h1H3 Copy

  
• IUPAC Standard InChIKey: QGZKDVFQNNGYKY-UHFFFAOYSA-N Copy
• CAS Registry Number: 7664-41-7
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • Ammonia-d3
• Other names: Ammonia gas; Nitro-Sil; Spirit of Hartshorn; NH3; Ammonia, anhydrous; Anhydrous ammonia; Aromatic Ammonia, Vaporole
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 146
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
  • Fluid Properties
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
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• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Gas phase thermochemistry data

Go To: Top, Phase change data, Henry's Law data, Gas phase ion energetics data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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View table.

Phase change data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Enthalpy of sublimation

Henry's Law data

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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to H₃N⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

H₂N^- +  =

By formula: H₂N^- + H⁺ = H₃N

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Timmermans, 1921
Timmermans, J., The Freezing Points of Organic Substances IV. New Exp. Determinations, Bull. Soc. Chim. Belg., 1921, 30, 62. [all data]

Fonseca and Lobo, 1989
Fonseca, I.M.A.; Lobo, L.Q., Thermodynamics of liquid mixtures of xenon and methyl fluoride, Fluid Phase Equilib., 1989, 47, 249. [all data]

Brunner, 1988
Brunner, E., Fluid Mixtures at High Pressures VI. Phase Separation and Critical Phenomena in 18 (n-Alkane + Ammonia) and 4 (n-Alkane _ Methanol) Mixtures, J. Chem. Thermodyn., 1988, 20, 273. [all data]

Hentze, 1977
Hentze, G., Critical temperature measurement of liquids by means of differential thermal analysis, Thermochim. Acta, 1977, 20, 27-30. [all data]

Zander and Thomas, 1979
Zander, Manfred; Thomas, Wilhelm, Some thermodynamic properties of liquid ammonia: PVT data, vapor pressure, and critical temperature, J. Chem. Eng. Data, 1979, 24, 1, 1-2, https://doi.org/10.1021/je60080a003 . [all data]

Overstreet and Giauque, 1937
Overstreet, Roy; Giauque, W.F., Ammonia. The Heat Capacity and Vapor Pressure of Solid and Liquid. Heat of Vaporization. The Entropy Values from Thermal and Spectroscopic Data, J. Am. Chem. Soc., 1937, 59, 2, 254-259, https://doi.org/10.1021/ja01281a008 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Qi, Sheng, et al., 1995
Qi, F.; Sheng, L.; Zhang, Y.; Yu, S.; Li, W.-K., Experimental and theoretical study of the dissociation energies D_O(H₂N-H) and D_O(H₂N⁺-H) and other related quantities, Chem. Phys. Lett., 1995, 234, 450. [all data]

Ruede, Troxler, et al., 1993
Ruede, R.; Troxler, H.; Beglinger, C.; Jungen, M., The dissociation energies of the positive ions NH₃⁺, NF₃⁺, PH₃⁺, PF₃⁺ and PCl₃⁺, Chem. Phys. Lett., 1993, 203, 477. [all data]

Reiser, Habenicht, et al., 1993
Reiser, G.; Habenicht, W.; Muller-Dethlefs, K., Zero kinetic energy (ZEKE) photoelectron spectroscopy of ammonia by nonresonant two-photon ionization from the neutral ground state, J. Chem. Phys., 1993, 98, 8462. [all data]

Locht, Hottmann, et al., 1992
Locht, R.; Hottmann, K.; Hagenow, G.; Denzer, W.; Baumgartel, H., The threhold-photoelectron spectrum of NH₃, Chem. Phys. Lett., 1992, 190, 124. [all data]

Locht, Leyh, et al., 1991
Locht, R.; Leyh, B.; Denzer, W.; Hagenow, G.; Baumgartel, H., The photoionization of ammonia revisited. The vibrational autoionization of NH₃ and its three isotopomers in the 10-12 eV photon energy range, Chem. Phys., 1991, 155, 407. [all data]

Habenicht, 1989
Habenicht, W., [Title unavailable], Ph.D. Thesis, Technische Universitat Munchen, 1989. [all data]

Baldwin, Loudon, et al., 1977
Baldwin, M.A.; Loudon, A.G.; Webb, K.S.; Cardnell, P.C., Charge location and fragmentation under electron impact. V-The ionization potentials of (methylated) phosphoramides, guanidines, formamides, acetamides, ureas and thioureas, Org. Mass Spectrom., 1977, 12, 279. [all data]

Debies and Rabalais, 1975
Debies, T.P.; Rabalais, J.W., Calculated photoionization cross-sections and angular distributions for the isoelectronic series Ne, HF, H₂O, NH₃, and CH₄, J. Am. Chem. Soc., 1975, 97, 487. [all data]

Aue, Webb, et al., 1975
Aue, D.H.; Webb, H.M.; Bowers, M.T., Photoelectron spectrum and gas-phase basicity of manxine. Evidence for a planar bridgehead nitrogen, J. Am. Chem. Soc., 1975, 97, 4136. [all data]

Morrison and Traeger, 1973
Morrison, J.D.; Traeger, J.C., Ionization and dissociation by electron impact. II. NH₃ and PH₃, Int. J. Mass Spectrom. Ion Phys., 1973, 11, 277. [all data]

Potts and Price, 1972
Potts, A.W.; Price, W.C., Photoelectron spectra and valence shell orbital structures of groups V VI hydrides, Proc. R. Soc. London A:, 1972, 326, 181. [all data]

Weiss and Lawrence, 1970
Weiss, M.J.; Lawrence, G.M., Photoelectron spectroscopy of NH₃ and ND₃ using molecular beams, J. Chem. Phys., 1970, 53, 214. [all data]

Branton, Frost, et al., 1969
Branton, G.R.; Frost, D.C.; Herring, F.G.; McDowell, C.A.; Stenhouse, I.A., The ionization potentials of ammonia and ammonia-d₃, measured by photoelectron spectroscopy, and an INDO calculation of these values, Chem. Phys. Lett., 1969, 3, 581. [all data]

Potapov, 1968
Potapov, V.K., Mechanism of ionic-molecular reactions, Dokl. Akad. Nauk SSSR, 1968, 183, 386, In original 843. [all data]

Chupka and Russell, 1968
Chupka, W.A.; Russell, M.E., Ion-molecule reactions of NH₃⁺ by photoionization, J. Chem. Phys., 1968, 48, 1527. [all data]

Dibeler, Walker, et al., 1966
Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M., Mass spectrometric study of photoionization. V.Water and ammonia, J.Res. NBS, 1966, 70A, 459. [all data]

Watanabe and Sood, 1965
Watanabe, K.; Sood, S.P., Absorption and photoionization coefficients of NH₃ in the 580-1650 A region, Sci. Light (Tokyo), 1965, 14, 36. [all data]

Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W., Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials, J. Chem. Soc., 1964, 4434. [all data]

Watanabe and Mottl, 1957
Watanabe, K.; Mottl, J.R., Ionization potentials of ammonia and some amines, J. Chem. Phys., 1957, 26, 1773. [all data]

Baumgartel, Jochims, et al., 1989
Baumgartel, H.; Jochims, H.-W.; Ruhl, E.; Bock, H.; Dammel, R.; Minkwitz, J.; Nass, R., Photoelectron and photoionization mass spectra of the fluoramines NH₃-_nF_n¹, Inorg. Chem., 1989, 28, 943. [all data]

Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Campbell, Liesegang, et al., 1979
Campbell, M.J.; Liesegang, J.; Riley, J.D.; Leckey, R.C.G.; Jenkin, J.G.; Poole, R.T., The electronic structure of the valence bands of solid NH₃ and H₂O studied by ultraviolet photoelectron spectroscopy, J. Electron Spectrosc. Relat. Phenom., 1979, 15, 83. [all data]

Daamen and Oskam, 1978
Daamen, H.; Oskam, A., Bonding properties of some monosubstituted chromium and tungsten hexacarbonyls M(CO)₅L (L=amine, substituted pyridine, azine), Inorg. Chim. Acta, 1978, 26, 81. [all data]

Muller and Schulz, 1990
Muller, U.; Schulz, G., Electron-impact dissociation of ammonia; formation of NH⁺ ions in excited states, Chem. Phys. Lett., 1990, 170, 401. [all data]

Locht, Servais, et al., 1988
Locht, R.; Servais, C.; Ligot, M.; Derwa, F.; Momigny, J., The dissociative electroionization of ammonia and ammonia-d3. I. The NH⁺ and NH₂⁺ dissociation channels, Chem. Phys., 1988, 123, 443. [all data]

Reed and Snedden, 1959
Reed, R.I.; Snedden, W., The ionisation potential of NH, J. Chem. Soc., 1959, 4132. [all data]

Powis, 1981
Powis, I., Influence of angular momentum in the dissociation of NH₃⁺, J. Chem. Soc. Faraday Trans. 2, 1981, 77, 1433. [all data]

McCulloh, 1976
McCulloh, K.E., Energetics and mechanisms of fragment ion formation in the photoionization of normal and deuterated water and ammonia, Int. J. Mass Spectrom. Ion Phys., 1976, 21, 333. [all data]

Foner and Hudson, 1958
Foner, S.N.; Hudson, R.L., Mass spectrometric detection of triazene and tetrazene and studies of the free radicals NH₂, and N₂H₃, J. Chem. Phys., 1958, 29, 442. [all data]

Wickham-Jones, Ervin, et al., 1989
Wickham-Jones, C.T.; Ervin, K.M.; Ellison, G.B.; Lineberger, W.C., NH2 Electron Affinity, J. Chem. Phys., 1989, 91, 4, 2762, https://doi.org/10.1063/1.456994 . [all data]

MacKay, Hemsworth, et al., 1976
MacKay, G.J.; Hemsworth, R.S.; Bohme, D.K., Absolute gas-phase acidities of CH₃NH₂, C₂H₅NH₂, (CH₃)₂NH, and (CH₃)₃N, Can. J. Chem., 1976, 54, 1624. [all data]

Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S., Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements, J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  Ptriple	Triple point pressure
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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