Nitrogen

• Formula: N₂
• Molecular weight: 28.0134
• IUPAC Standard InChI: InChI=1S/N2/c1-2 Copy

  
• IUPAC Standard InChIKey: IJGRMHOSHXDMSA-UHFFFAOYSA-N Copy
• CAS Registry Number: 7727-37-9
• 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.
• Other names: Nitrogen gas; N2; UN 1066; UN 1977; Dinitrogen; Molecular nitrogen; Diatomic nitrogen; Nitrogen-14
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• 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 150, reactions 151 to 156
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • Constants of diatomic molecules
  • Fluid Properties
• Data at other public NIST sites:
  • Electron-Impact Ionization Cross Sections (on physics web site)
  • Gas Phase Kinetics Database
• Options:
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• 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 (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/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 (atm)
    T = temperature (K)

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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:
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 N₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

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]

Jacobsen, Stewart, et al., 1986
Jacobsen, R.T.; Stewart, R.B.; Jahangiri, M., Termodynamic Properties of Nitrogen from the Freezing Line to 2000 K at Pressures to 1000 MPa, J. Phys. Chem. Ref. Data, 1986, 15, 735-909. [all data]

Streng, 1971
Streng, A.G., Miscibility and Compatibility of Some Liquid and Solidified Gases at Low Temperature, J. Chem. Eng. Data, 1971, 16, 357. [all data]

Angus, de Reuck, et al., 1979
Angus, S.; de Reuck, K.M.; Armstrong, B.; Jacobsen, R.T.; Stewart, R.B., International Thermodynamic Tables of the Fluid State - 6 Nitrogen, Pergamon, New York, 1979. [all data]

Henning and Otto, 1936
Henning, F.; Otto, J., Vapor pressure curves and triple points in the temperature region from 14 to 90 k, Phys. Z., 1936, 37, 633-8. [all data]

Giauque and Clayton, 1933
Giauque, W.F.; Clayton, J.O., Heat Capacity and Entropy of Nitrogen. Heat of Vaporization. Vapor Pressure of Solid and Liquid. The Reaction 1/2 N2 + 1/2 O2 = NO from Spectroscopic Data, J. Am. Chem. Soc., 1933, 55, 4875. [all data]

Weber, 1970
Weber, L.A., Some vapor pressure and P,V,T data on nitrogen in t he range 65 to 140 K, J. Chem. Thermodyn., 1970, 2, 839-846. [all data]

Cardoso, 1915
Cardoso, E., Study of the Critical Point of Several Difficultly LIquifiable Gases: Nitrogen, Carbon Monoxide, Oxygen and Methane, J. Chim. Phys. Phys.-Chim. Biol., 1915, 13, 312. [all data]

Edejer and Thodos, 1967
Edejer, Merardo P.; Thodos, George, Vapor pressures of liquid nitrogen between the triple and critical points, J. Chem. Eng. Data, 1967, 12, 2, 206-209, https://doi.org/10.1021/je60033a014 . [all data]

Giauque and Clayton, 1933, 2
Giauque, W.F.; Clayton, J.O., The Heat Capacity and Entropy of Nitrogen. Heat of Vaporization. Vapor Pressures of Solid and Liquid. The Reaction 1/2 N ₂ + 1/2 O ₂ = NO from Spectroscopic Data, J. Am. Chem. Soc., 1933, 55, 12, 4875-4889, https://doi.org/10.1021/ja01339a024 . [all data]

Moussa, Muijlwijk, et al., 1966
Moussa, M.R.; Muijlwijk, R.; van Dijk, H., The Vapour Pressure of Liquid Nitrogen, Physica (Amsterdam), 1966, 32, 5, 900-912, https://doi.org/10.1016/0031-8914(66)90021-8 . [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]

Trickl, Cromwell, et al., 1989
Trickl, T.; Cromwell, E.F.; Lee, Y.T.; Kung, A.H., State-selective ionization of nitrogen in the X₂ =0 and v =1 states by two-color (1+1) photon excitation near threshold, J. Chem. Phys., 1989, 91, 6006. [all data]

Stephen, Mark, et al., 1984
Stephen, K.; Mark, T.D.; Futrell, J.H.; Helm, H., Electron impact ionization of (N₂)₂: Appearance energies of N₃⁺ and N₄⁺, J. Chem. Phys., 1984, 80, 3185. [all data]

Grade, Wienecke, et al., 1983
Grade, M.; Wienecke, J.; Rosinger, W.; Hirschwald, W., Electron impact investigation of the molecules SeS(g) and TeSe(g) under high-temperature equilibrium conditions, Ber. Bunsen-Ges. Phys. Chem., 1983, 87, 355. [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]

Armentrout, Tarr, et al., 1981
Armentrout, P.B.; Tarr, S.M.; Dori, A.; Freund, R.S., Electron impact ionization cross section of metastable N₂ (A₂Σu⁺), J. Chem. Phys., 1981, 75, 2788. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Sahini, Constantin, et al., 1978
Sahini, V.E.; Constantin, V.; Serban, I., Determination of ionization potentials using a MI-1305 mass spectrometer, Rev. Roum. Chim., 1978, 23, 479. [all data]

Rabalais, Debies, et al., 1974
Rabalais, J.W.; Debies, T.P.; Berkosky, J.L.; Huang, J.-T.J.; Ellison, F.O., Calculated photoionization cross sections relative experimental photoionization intensities for a selection of small molecules, J. Chem. Phys., 1974, 61, 516. [all data]

Lee and Rabalais, 1974
Lee, T.H.; Rabalais, J.W., Vibrational transition probabilities in photoelectron spectra, J. Chem. Phys., 1974, 61, 2747. [all data]

Natalis, 1973
Natalis, P., Contribution a la spectroscopie photoelectronique. Effets de l'autoionisation dans less spectres photoelectroniques de molecules diatomiques et triatomiques, Acad. R. Belg. Mem. Cl. Sci. Collect. 8, 1973, 41, 1. [all data]

Hotop and Niehaus, 1970
Hotop, H.; Niehaus, A., Reactions of excited atoms and molecules with atoms and molecules. V.Comparison of Penning electron and photoelectron spectra of H₂, N₂ and CO, Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 415. [all data]

Cermak, 1968
Cermak, V., Penning ionization electron spectroscopy. I. Determination of ionization potentials of polyatomic molecules, Collection Czech. Chem. Commun., 1968, 33, 2739. [all data]

Cook and Metzger, 1964
Cook, G.R.; Metzger, P.H., Photoionization and absorption cross sections of O₂ and N₂ in the 600- to 1000-A region, J. Chem. Phys., 1964, 41, 321. [all data]

Ogawa and Tanaka, 1962
Ogawa, M.; Tanaka, Y., Rydberg absorption series of N₂, Can. J. Phys., 1962, 40, 1593. [all data]

Worley, 1943
Worley, R.E., Absorption spectrum of N₂ in the extreme ultraviolet, Phys. Rev., 1943, 64, 207. [all data]

Worley and Jenkins, 1938
Worley, R.E.; Jenkins, F.A., A new Rydberg series in N₂, Phys. Rev., 1938, 54, 305. [all data]

Potts and Williams, 1974
Potts, A.W.; Williams, T.A., The observation of "forbidden" transitions in He II photoelectron spectra, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 3. [all data]

Katrib, Debies, et al., 1973
Katrib, A.; Debies, T.P.; Colton, R.J.; Lee, T.H.; Rabalais, J.W., The use of differential photoionization cross sections as a function of excitation energy in assigning photoelectron spectra, Chem. Phys. Lett., 1973, 22, 196. [all data]

Locht, Schopman, et al., 1975
Locht, R.; Schopman, J.; Wankenne, H.; Momigny, J., The dissociative ionization of nitrogen, Chem. Phys., 1975, 7, 393. [all data]

Smyth, Schiavone, et al., 1973
Smyth, K.C.; Schiavone, J.A.; Freund, R.S., Dissociative excitation of N₂ by electron impact: Translational spectroscopy of long-lived high- Rydberg fragment atoms, J. Chem. Phys., 1973, 59, 5225. [all data]

Crowe and McConkey, 1973
Crowe, A.; McConkey, J.W., Dissociative ionization by electron impact II. N⁺ N⁺⁺ from N₂, J. Phys. B:, 1973, 6, 2108. [all data]

Hierl and Franklin, 1967
Hierl, P.M.; Franklin, J.L., Appearance potentials and kinetic energies of ions from N₂, CO, and NO, J. Chem. Phys., 1967, 47, 3154. [all data]

Frost and McDowell, 1956
Frost, D.C.; McDowell, C.A., The dissociation energy of the nitrogen molecule, Proc. Roy. Soc. (London), 1956, A236, 278. [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)
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔvapH	Enthalpy of vaporization
  ρc	Critical density

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