Nitrogen dioxide

Formula: NO₂
Molecular weight: 46.0055
IUPAC Standard InChI: InChI=1S/NO2/c2-1-3
IUPAC Standard InChIKey: JCXJVPUVTGWSNB-UHFFFAOYSA-N
CAS Registry Number: 10102-44-0
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 oxide; Nitrito; Nitro; Nitrogen peroxide; Azote; Rcra waste number P078; Stickstoffdioxid; Stikstofdioxyde; Nitrogen dioxide (NO2)
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Phase change data

Go To: Top, Gas phase ion energetics data, References, Notes

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

Quantity	Value	Units	Method	Reference	Comment
T_boil	295.08	K	N/A	Thorpe, 1880	Uncertainty assigned by TRC = 0.5 K; TRC

Antoine Equation Parameters

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

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Temperature (K)	A	B	C	Reference	Comment
217.6 to 294.	3.34677	540.635	-131.93	Stull, 1947	Coefficents calculated by NIST from author's data.

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:

Gas phase ion energetics data

Go To: Top, Phase change data, References, Notes

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 NO₂⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	9.586 ± 0.002	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	141.3	kcal/mol	N/A	Hunter and Lias, 1998	HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	133.9	kcal/mol	N/A	Hunter and Lias, 1998	HL

Electron affinity determinations

EA (eV)	Method	Reference	Comment
2.2730 ± 0.0050	LPES	Ervin, Ho, et al., 1988	B
2.30 ± 0.10	IMRE	Chowdhury, Heinis, et al., 1986	ΔGea(423 K) = -52.6 kcal/mol; ΔSea (estimated) = -0.82 eu.; B
2.275 ± 0.025	LPD	Woo, Helmy, et al., 1981	B
2.36 ± 0.10	LPES	Herbst, Patterson, et al., 1974	B
2.35 ± 0.10	LPD	Smith, Lee, et al., 1979	B
2.40 ± 0.10	CIDT	Tiernan and Wu, 1978	B
2.28 ± 0.10	IMRB	Hughes, Lifschitz, et al., 1973	B
2.380 ± 0.060	IMRB	Dunkin, Fehsenfeld, et al., 1972	B
2.30 ± 0.15	Endo	Lifshitz, Hughes, et al., 1970	B
2.11 ± 0.18	ECD	Chen and Wentworth, 1983	B
2.800 ± 0.050	LPD	Richardson, Stephenson, et al., 1974	See also Pearson, Schaefer, et al., 1974; B
1.800 ± 0.050	LPD	Richardson, Stephenson, et al., 1974	B
<2.59998	IMRB	Ferguson, Dunkin, et al., 1972	B
1.80 ± 0.20	NBIE	Durup, Parlant, et al., 1977	B
2.09999	Endo	Refaey, 1976	B
2.500 ± 0.050	NBIE	Leffert, Jackson, et al., 1973	B
>2.50 ± 0.10	NBIE	Nalley, Compton, et al., 1973	B
2.50 ± 0.10	NBIE	Baeda, 1972	B
2.03998	Endo	Berkowitz, Chupka, et al., 1971	B
2.07 ± 0.24	IMRB	Vogt, 1969	B
3.100 ± 0.050	PD	Warneck, 1969	B
3.90 ± 0.20	EIAE	Tsuda and Hamill, 1964	From MeNO₂, EtNO₂; B
>3.81995	IMRB	Curran, 1962	B
3.9895	SI	Farragher, Page, et al., 1964	The Magnetron method, lacking mass analysis, is not considered reliable.; B

Ionization energy determinations

IE (eV)	Method	Reference	Comment
9.60 ± 0.03	END	Clemmer and Armentrout, 1992	LL
9.586 ± 0.002	LS	Haber, Zwanziger, et al., 1988	LL
11.23	PE	Kimura, Katsumata, et al., 1981	LLK
10.4 ± 0.3	EI	Stephan, Helm, et al., 1980	LLK
≤9.62 ± 0.01	PI	Killgoar, Leroi, et al., 1973	LLK
9.75 ± 0.01	PI	Dibeler and Walker, 1967	RDSH
11.23	PE	Katsumata, Shiromaru, et al., 1982	Vertical value; LBLHLM

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
NO⁺	12.34	O	PI	Dibeler and Walker, 1967	RDSH
O⁺	16.82	NO	PI	Dibeler, Walker, et al., 1967	RDSH

Anion protonation reactions

+ =

By formula: NO₂^- + H⁺ = HNO₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	340.23 ± 0.21	kcal/mol	D-EA	Ervin, Ho, et al., 1988	gas phase; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	333.73 ± 0.31	kcal/mol	H-TS	Ervin, Ho, et al., 1988	gas phase; B

References

Go To: Top, Phase change data, Gas phase ion energetics data, Notes

Thorpe, 1880
Thorpe, T.E., On the Relation Between the Molecular Weights of Substances and their Specific Gravities in the Liquid State, J. Chem. Soc., 1880, 37, 141. [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]

Ervin, Ho, et al., 1988
Ervin, K.M.; Ho, J.; Lineberger, W.C., Ultraviolet Photoelectron Spectrum of NO₂^-, J. Phys. Chem., 1988, 92, 19, 5405, https://doi.org/10.1021/j100330a017 . [all data]

Chowdhury, Heinis, et al., 1986
Chowdhury, S.; Heinis, T.; Grimsrud, E.P.; Kebarle, P., Entropy Changes and Electron Affinities from Gas-Phase Electron Transfer Equilibria: A^- + B = A + B^-, J. Phys. Chem., 1986, 90, 12, 2747, https://doi.org/10.1021/j100403a037 . [all data]

Woo, Helmy, et al., 1981
Woo, S.B.; Helmy, E.M.; Mauk, P.H.; Paszek, A.P., Wide Range Absolute Photodetachment Spectrum of NO₂^-, Phys. Rev. A, 1981, 24, 3, 1380, https://doi.org/10.1103/PhysRevA.24.1380 . [all data]

Herbst, Patterson, et al., 1974
Herbst, E.; Patterson, T.A.; Lineberger, W.C., Laser photodetachment of NO₂-, J. Chem. Phys., 1974, 61, 1300. [all data]

Smith, Lee, et al., 1979
Smith, G.P.; Lee, L.C.; Moseley, J.T., Photodissociation and photodetachment of molecular negative ions. VIII. Nitrogen oxides and hydrates,3500-8250 Å, J. Chem. Phys., 1979, 71, 4034. [all data]

Tiernan and Wu, 1978
Tiernan, T.O.; Wu, R.L.C., Thermochemical Data for Molecular Negative Ions from Collisional Dissociation Thresholds, Adv. Mass Spectrom., 1978, 7A, 136. [all data]

Hughes, Lifschitz, et al., 1973
Hughes, B.M.; Lifschitz, C.; Tiernan, T.O., Electron affinities from endothermic negative-ion charge-transfer reactions. III. NO, NO₂, S₂, CS₂, Cl₂, Br₂, I₂, and C₂H, J. Chem. Phys., 1973, 59, 3162. [all data]

Dunkin, Fehsenfeld, et al., 1972
Dunkin, D.B.; Fehsenfeld, F.C.; Ferguson, F.E., Thermal energy rate constants for the reactions NO₂^- + Cl₂ → Cl₂^-, Cl₂^- + NO₂ Ü Cl^-, HS^- + NO₂ Ü NO₂^-, HS^- + Cl₂ Ü Cl₂^-, and S^- + NO₂ Ü NO₂^-, Chem. Phys. Lett., 1972, 15, 257. [all data]

Lifshitz, Hughes, et al., 1970
Lifshitz, C.; Hughes, B.M.; Tiernan, T.O., Electron Affinities for Endothermic Negative Ion Charge Transfer Reactions: NO₂ and SF₆, Chem. Phys. Lett., 1970, 7, 4, 469, https://doi.org/10.1016/0009-2614(70)80339-6 . [all data]

Chen and Wentworth, 1983
Chen, E.C.M.; Wentworth, W.E., Determination of molecular electron affinities using the electron capture detector in the pulse sampling mode at steady state, J. Phys. Chem., 1983, 87, 45. [all data]

Richardson, Stephenson, et al., 1974
Richardson, J.H.; Stephenson, L.M.; Brauman, J.I., Photodetachment of NO₂-: Experimental evidence for a new isomer, Chem. Phys. Lett., 1974, 25, 318. [all data]

Pearson, Schaefer, et al., 1974
Pearson, P.K.; Schaefer, H.F., III; Richardson, J.H.; Stephenson, L.M.; Brauman, J.I., Three isomers of the NO₂- ion, J. Am. Chem. Soc., 1974, 96, 6778. [all data]

Ferguson, Dunkin, et al., 1972
Ferguson, E.E.; Dunkin, D.B.; Fehsenfeld, F.C., Reactions of NO₂^- and NO₃^- with HCl and HBr, J. Chem. Phys., 1972, 57, 1459. [all data]

Durup, Parlant, et al., 1977
Durup, M.; Parlant, G.; Appell, J.; Durup, J.; Ozenne, J.-B., Translational spectroscopy of neutralization-reionization double collision processes of Ar⁺ ions at keV energies, Chem. Phys., 1977, 25, 245. [all data]

Refaey, 1976
Refaey, K.M.A., Endoergic ion-molecule-Collision Processes of Negative Ions. IV. Collisions of I- on NO₂, N₂O and NO, Int. J. Mass Spectrom. Ion Phys., 1976, 21, 21. [all data]

Leffert, Jackson, et al., 1973
Leffert, C.B.; Jackson, W.M.; Rothe, E.W., Measurement of the electron affinity of NO₂, J. Chem. Phys., 1973, 58, 5801. [all data]

Nalley, Compton, et al., 1973
Nalley, S.J.; Compton, R.N.; Schweinler, H.C.; Anderson, V.E., Molecular electron affinities from collisional ionization of cesium. I. NO, NO₂, and N₂O, J. Chem. Phys., 1973, 59, 4125. [all data]

Baeda, 1972
Baeda, A.P.M., The adiabatic electron affinities of Cl₂, Br₂, I₂, IBr, NO₂, and O₂, Physica, 1972, 59, 541. [all data]

Berkowitz, Chupka, et al., 1971
Berkowitz, J.; Chupka, W.A.; Gutman, D., Electron Affinities of O₂, O₃, NO, NO₂, and NO₃ by Endothermic Charge Transfer, J. Chem. Phys., 1971, 55, 6, 2733, https://doi.org/10.1063/1.1676488 . [all data]

Vogt, 1969
Vogt, D., Uber die Energieanhangigkeit und den Mechanismus von Reaktionen bei Stossen Langsamer Negativer Ionen auf Molekule, Int. J. Mass Spectrom. Ion Phys., 1969, 3, 1-2, 81, https://doi.org/10.1016/0020-7381(69)80062-8 . [all data]

Warneck, 1969
Warneck, P., Photodetachment of NO₂^-, Chem. Phys. Lett., 1969, 3, 7, 532, https://doi.org/10.1016/0009-2614(69)85054-2 . [all data]

Tsuda and Hamill, 1964
Tsuda, S.; Hamill, W.H., Ionization Efficiency Measurements by the Retarding Potential Difference Method, Adv. Mass Spectrom., 1964, 3, 249. [all data]

Curran, 1962
Curran, R.K., Formation of NO₂^- by Charge Transfer at Very Low Energies, Phys. Rev., 1962, 125, 3, 910, https://doi.org/10.1103/PhysRev.125.910 . [all data]

Farragher, Page, et al., 1964
Farragher, A.L.; Page, F.M.; Wheeler, R.C., Electron Affinities of the Nitrogen Oxides, Disc. Faraday Soc., 1964, 37, 203, https://doi.org/10.1039/df9643700203 . [all data]

Clemmer and Armentrout, 1992
Clemmer, D.E.; Armentrout, P.B., Direct determination of the adiabatic ionization energy of NO₂ as measured by guided ion-beam mass spectrometry, J. Chem. Phys., 1992, 97, 2451. [all data]

Haber, Zwanziger, et al., 1988
Haber, K.S.; Zwanziger, F.X.; Campos, R.T.; Wiedmann, R.T.; Grant, E.R., Direct determination of the adiabatic ionization potential of NO₂ by multiresonant optical absorption, Chem. Phys. Lett., 1988, 144, 58. [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]

Stephan, Helm, et al., 1980
Stephan, K.; Helm, H.; Kim, Y.B.; Seykora, G.; Ramler, J.; Grossl, M.; Mark, E.; Mark, T.D., Single and double ionization of nitrogen dioxide by electron impact from threshold up to 180 eV, J. Chem. Phys., 1980, 73, 303. [all data]

Killgoar, Leroi, et al., 1973
Killgoar, P.C., Jr.; Leroi, G.E.; Chupka, W.A.; Berkowitz, J., Photoionization study of NO₂. I. The ionization potential, J. Chem. Phys., 1973, 59, 1370. [all data]

Dibeler and Walker, 1967
Dibeler, V.H.; Walker, J.A., Mass spectrometric study of the photoionization of small polyatomic molecules, Advan. Mass Spectrom., 1967, 4, 767. [all data]

Katsumata, Shiromaru, et al., 1982
Katsumata, S.; Shiromaru, H.; Mitani, K.; Iwata, S.; Kimura, K., Photoelectron angular distribution and assignments of photoelectron spectra of nitrogen dioxide, nitromethane and nitrobenzene, Chem. Phys., 1982, 69, 423. [all data]

Dibeler, Walker, et al., 1967
Dibeler, V.H.; Walker, J.A.; Liston, S.K., Mass spectrometric study of photoionization. VII.Nitrogen dioxide and nitrous oxide, J.Res. NBS, 1967, 71A, 371. [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, References

Symbols used in this document:

AE	Appearance energy
EA	Electron affinity
IE (evaluated)	Recommended ionization energy
T_boil	Boiling point
Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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