Nitrogen
- Formula: N2
- Molecular weight: 28.0134
- IUPAC Standard InChIKey: IJGRMHOSHXDMSA-UHFFFAOYSA-N
- 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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Gas phase thermochemistry data
Go To: Top, 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.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
S°gas,1 bar | 45.7957 ± 0.001 | cal/mol*K | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
S°gas,1 bar | 45.796 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in March, 1977 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = 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
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 100. to 500. | 500. to 2000. | 2000. to 6000. |
---|---|---|---|
A | 6.927919 | 4.662006 | 8.489178 |
B | 0.443111 | 4.753120 | 0.269772 |
C | -2.305798 | -2.055099 | -0.046870 |
D | 3.975949 | 0.327386 | 0.003504 |
E | 0.000028 | 0.126100 | -1.088375 |
F | -2.072637 | -1.179542 | -4.534157 |
G | 54.11491 | 50.76243 | 53.77175 |
H | 0.0 | 0.0 | 0.0 |
Reference | Chase, 1998 | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in March, 1977; New parameter fit January 2009 | Data last reviewed in March, 1977; New parameter fit January 2009 | Data last reviewed in March, 1977; New parameter fit January 2009 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 15.581 ± 0.008 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 118.0 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 111.0 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
15.581 ± 0.008 | S | Trickl, Cromwell, et al., 1989 | LL |
15.7 ± 0.1 | EI | Stephen, Mark, et al., 1984 | LBLHLM |
15.6 ± 0.1 | EI | Grade, Wienecke, et al., 1983 | LBLHLM |
15.60 | PE | Kimura, Katsumata, et al., 1981 | LLK |
10.1 ± 0.6 | EI | Armentrout, Tarr, et al., 1981 | LLK |
15.58 | EI | Armentrout, Tarr, et al., 1981 | LLK |
15.5808 | EVAL | Huber and Herzberg, 1979 | LLK |
15.58 ± 0.02 | EI | Sahini, Constantin, et al., 1978 | LLK |
15.5 | PI | Rabalais, Debies, et al., 1974 | LLK |
15.58 | PE | Lee and Rabalais, 1974 | LLK |
15.61 | PE | Natalis, 1973 | LLK |
15.58 ± 0.01 | PE | Hotop and Niehaus, 1970 | RDSH |
15.56 | CI | Cermak, 1968 | RDSH |
15.58 | PI | Cook and Metzger, 1964 | RDSH |
15.5803 | S | Ogawa and Tanaka, 1962 | RDSH |
15.5802 | S | Worley, 1943 | RDSH |
15.5812 ± 0.0002 | S | Worley and Jenkins, 1938 | RDSH |
15.58 | PE | Potts and Williams, 1974 | Vertical value; LLK |
15.60 | PE | Katrib, Debies, et al., 1973 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
N+ | 24.34 | N(4So) | EI | Locht, Schopman, et al., 1975 | LLK |
N+ | 24.3 | N | EI | Smyth, Schiavone, et al., 1973 | LLK |
N+ | 24.4 ± 0.25 | N | EI | Crowe and McConkey, 1973 | LLK |
N+ | 24.32 ± 0.03 | N | EI | Hierl and Franklin, 1967 | RDSH |
N+ | 48. ± 2. | N+ | EI | Hierl and Franklin, 1967 | RDSH |
N+ | 24.32 ± 0.02 | N | EI | Frost and McDowell, 1956 | RDSH |
References
Go To: Top, Gas phase thermochemistry 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]
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, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy S°gas,1 bar Entropy of gas at standard conditions (1 bar) - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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