Amino radical

• Formula: H₂N
• Molecular weight: 16.0226
• IUPAC Standard InChI: InChI=1S/H2N/h1H2 Copy

  
• IUPAC Standard InChIKey: MDFFNEOEWAXZRQ-UHFFFAOYSA-N Copy
• CAS Registry Number: 13770-40-6
• 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.
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• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Data at other public NIST sites:
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Gas phase thermochemistry 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.

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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Reaction thermochemistry 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: John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

HN^- +  =

By formula: HN^- + H⁺ = H₂N

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and 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 H₂N⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

HN^- +  =

By formula: HN^- + H⁺ = H₂N

Vibrational and/or electronic energy levels

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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.

Data compiled by: Marilyn E. Jacox

State:   Ryd

State:   A

State:   X

Additional references: Jacox, 1994, page 21; Jacox, 1998, page 133; Jacox, 2003, page 18; Dixon, 1965; Halpern, Hancock, et al., 1975; Hills and McKellar, 1979, 2; Donnelly, Baronavski, et al., 1979; Jungen, Hallin, et al., 1980; Muenchausen, Hills, et al., 1985; Kanada, Yamamoto, et al., 1991; Tonooka, Yamamoto, et al., 1997; Morino and Kawaguchi, 1997; Ozeki and Saito, 1998; Muller, Klein, et al., 1999; Petrongolo, Fan, et al., 2003; Duxbury and Reid, 2007

Notes

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, Notes

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

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

Neumark, Lykke, et al., 1985
Neumark, D.M.; Lykke, K.R.; Anderson, T.; Lineberger, W.C., Infrared Spectrum and Autodetachment Dynamics of NH-, J. Chem. Phys., 1985, 83, 9, 4364, https://doi.org/10.1063/1.449052 . [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]

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]

Celotta, Bennett, et al., 1974
Celotta, R.S.; Bennett, R.A.; Hall, J.L., Laser Photodetachment Determination of the Electron Affinities of OH, NH₂, NH, SO₂, and S₂, J. Chem. Phys., 1974, 60, 5, 1740, https://doi.org/10.1063/1.1681268 . [all data]

Smyth and Brauman, 1972
Smyth, K.C.; Brauman, J.I., Photodetachment of electrons from amide and arsenide ions: The electron affinities of NH₂ and AsH₂., J. Chem. Phys., 1972, 56, 4620. [all data]

Feldman, 1971
Feldman, D., Photoablosung von Elektronen bei Si^- und NH₂^-, Z. Naturforsch. A, 1971, 26, 1100. [all data]

Smyth, McIver, et al., 1971
Smyth, K.C.; McIver, R.T.; Brauman, J.I.; Wallace, R.W., Photodetachment of negative ions using a continuously tunable laser and an ICR spectrometer, J. Chem. Phys., 1971, 54, 2758. [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]

Page and Goode, 1969
Page, F.M.; Goode, G.C., Negative Ions and the Magnetron., Wiley, NY, 1969. [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]

Gibson, Greene, et al., 1985
Gibson, S.; Greene, J.; Berkowitz, J., Photoionization of the amidogen radical, J. Chem. Phys., 1985, 83, 4319. [all data]

Dunlavey, Dyke, et al., 1980
Dunlavey, S.J.; Dyke, J.M.; Jonathan, N.; Morris, A., Vacuum ultraviolet photoelectron spectroscopy of transient species. Part 11. The NH₂(X(2)B1) radical, Mol. Phys., 1980, 39, 1121. [all data]

Melton, 1966
Melton, C.E., Study by mass spectrometry of the decomposition of ammonia by ionizing radiation in a wide-range radiolysis source, J. Chem. Phys., 1966, 45, 4414. [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]

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]

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]

Dressler and Ramsay, 1959
Dressler, K.; Ramsay, D.A., The Electronic Absorption Spectra of NHFormula and NDFormula, Phil. Trans. Roy. Soc. (London) A251, 1959, 251, 1002, 553, https://doi.org/10.1098/rsta.1959.0011 . [all data]

Kroll, 1975
Kroll, M., The fluorescence spectrum of NH2 excited by a cw dye laser, J. Chem. Phys., 1975, 63, 1, 319, https://doi.org/10.1063/1.431101 . [all data]

Johns, Ramsay, et al., 1976
Johns, J.W.C.; Ramsay, D.A.; Ross, S.C., The absorption spectrum of NH, Can. J. Phys., 1976, 54, 17, 1804, https://doi.org/10.1139/p76-213 . [all data]

Vervloet, 1988
Vervloet, M., Study of the electronic ground state of NH, Mol. Phys., 1988, 63, 3, 433, https://doi.org/10.1080/00268978800100311 . [all data]

Ross, Birss, et al., 1988
Ross, S.C.; Birss, F.W.; Vervloet, M.; Ramsay, D.A., The absorption spectrum of NH2 in the region 5300 to 6800 Å, J. Mol. Spectrosc., 1988, 129, 2, 436, https://doi.org/10.1016/0022-2852(88)90048-3 . [all data]

Dixon, Irving, et al., 1991
Dixon, R.N.; Irving, S.J.; Nightingale, J.R.; Vervloet, M., J. Chem. Soc., 1991, Faraday Trans. 87, 2121. [all data]

Schleipen, ter Meulen, et al., 1992
Schleipen, J.; ter Meulen, J.J.; Nemes, L.; Vervloet, M., New vibronic states of NH2 observed in ammonia photolysis, Chem. Phys. Lett., 1992, 197, 1-2, 165, https://doi.org/10.1016/0009-2614(92)86041-F . [all data]

Hadj Bachir, Huet, et al., 1999
Hadj Bachir, I.; Huet, T.R.; Destombes, J.-L.; Vervloet, M., A Combined Analysis of Laser Optogalvanic and Fourier Transform Emission Spectra of NH2near its Barrier to Linearity, J. Mol. Spectrosc., 1999, 193, 2, 326, https://doi.org/10.1006/jmsp.1998.7752 . [all data]

Loomis, Reid, et al., 2000
Loomis, R.A.; Reid, J.P.; Leone, S.R., Photofragmentation of ammonia at 193.3 nm: Bimodal rotational distributions and vibrational excitation of NH[sub 2](A), J. Chem. Phys., 2000, 112, 2, 658, https://doi.org/10.1063/1.480677 . [all data]

Xin, Fan, et al., 2003
Xin, J.; Fan, H.; Ionescu, I.; Annesley, C.; Reid, S.A., Fluorescence excitation spectroscopy of the system of jet-cooled NH2 in the region 2900--4300Å, J. Mol. Spectrosc., 2003, 219, 1, 37, https://doi.org/10.1016/S0022-2852(03)00008-0 . [all data]

Blindauer, Peric, et al., 1993
Blindauer, C.; Peric, M.; Schurath, U., The Visible Absorption Spectrum of Matrix-Isolated NH2 and Its Deuterides - Comparison with Calculated Spectroscopic Properties, J. Mol. Spectrosc., 1993, 158, 1, 177, https://doi.org/10.1006/jmsp.1993.1065 . [all data]

Robinson and McCarty, 1959
Robinson, G.W.; McCarty, M., Jr., Trapped NH2 Radicals at 4.2°K, J. Chem. Phys., 1959, 30, 4, 999, https://doi.org/10.1063/1.1730143 . [all data]

Robinson, 1962
Robinson, G.W., Free Radicals in Inorganic Chemistry, Advan. Chem. Ser. 36, Amer. Chem. Soc., 1962. [all data]

Milligan and Jacox, 1965
Milligan, D.E.; Jacox, M.E., Matrix-Isolation Infrared Spectrum of the Free Radical NH2, J. Chem. Phys., 1965, 43, 12, 4487, https://doi.org/10.1063/1.1696721 . [all data]

Vervloet and Merienne-Lafore, 1982
Vervloet, M.; Merienne-Lafore, M.F., Constantes moléculaires de de NH, Can. J. Phys., 1982, 60, 1, 49, https://doi.org/10.1139/p82-007 . [all data]

Amano, Bernath, et al., 1982
Amano, T.; Bernath, P.F.; McKellar, A.R.W., Direct observation of the ν1 and ν3 fundamental bands of NH2 by difference frequency laser spectroscopy, J. Mol. Spectrosc., 1982, 94, 1, 100, https://doi.org/10.1016/0022-2852(82)90297-1 . [all data]

McKellar, Vervloet, et al., 1990
McKellar, A.R.W.; Vervloet, M.; Burkholder, J.B.; Howard, C.J., A combined analysis of the ν1, ν3, and 2ν2 vibrational states of the NH2 radical using Fourier transform absorption and emission data, J. Mol. Spectrosc., 1990, 142, 2, 319, https://doi.org/10.1016/0022-2852(90)90186-T . [all data]

Vervloet, Merienne-Lafore, et al., 1978
Vervloet, M.; Merienne-Lafore, M.F.; Ramsay, D.A., Molecular constants for the 010 level of the 2B1 ground state of NH2, Chem. Phys. Lett., 1978, 57, 1, 5, https://doi.org/10.1016/0009-2614(78)80340-6 . [all data]

Hills and McKellar, 1979
Hills, G.W.; McKellar, A.R.W., Laser magnetic resonance spectra of NH2 in the 9-μm region, J. Mol. Spectrosc., 1979, 74, 2, 224, https://doi.org/10.1016/0022-2852(79)90053-5 . [all data]

Kawaguchi, Yamada, et al., 1980
Kawaguchi, K.; Yamada, C.; Hirota, E.; Brown, J.M.; Buttenshaw, J.; Parent, C.R.; Sears, T.J., The laser magnetic resonance spectrum of the ν2 band of NH2, J. Mol. Spectrosc., 1980, 81, 1, 60, https://doi.org/10.1016/0022-2852(80)90329-X . [all data]

Burkholder, Howard, et al., 1988
Burkholder, J.B.; Howard, C.J.; McKellar, A.R.W., Fourier transform infrared spectrum of the ν2 band of the NH2 radical, J. Mol. Spectrosc., 1988, 127, 2, 415, https://doi.org/10.1016/0022-2852(88)90131-2 . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]

Dixon, 1965
Dixon, R.N., The Renner effect in nearly linear molecule, with application to NH, Mol. Phys., 1965, 9, 4, 357, https://doi.org/10.1080/00268976500100491 . [all data]

Halpern, Hancock, et al., 1975
Halpern, J.B.; Hancock, G.; Lenzi, M.; Welge, K.H., Laser induced fluorescence from NH2(2A1). State selected radiative lifetimes and collisional de-excitation rates, J. Chem. Phys., 1975, 63, 11, 4808, https://doi.org/10.1063/1.431223 . [all data]

Hills and McKellar, 1979, 2
Hills, G.W.; McKellar, A.R.W., Laser magnetic resonance spectrum of the ν2 band of ND2, J. Chem. Phys., 1979, 71, 8, 3330, https://doi.org/10.1063/1.438775 . [all data]

Donnelly, Baronavski, et al., 1979
Donnelly, V.M.; Baronavski, A.P.; McDonald, J.R., Excited state dynamics and bimolecular quenching processes for NH2(Ã2A1), Chem. Phys., 1979, 43, 2, 283, https://doi.org/10.1016/0301-0104(79)85195-2 . [all data]

Jungen, Hallin, et al., 1980
Jungen, Ch.; Hallin, K-E.J.; Merer, A.J., Mol. Phys., 1980, 40, 25, 65. [all data]

Muenchausen, Hills, et al., 1985
Muenchausen, R.E.; Hills, G.W.; Merienne-Lafore, M.F.; Ramsay, D.A.; Vervloet, M.; Birss, F.W., Further studies of the electronic and vibrational spectra of ND2, J. Mol. Spectrosc., 1985, 112, 1, 203, https://doi.org/10.1016/0022-2852(85)90204-8 . [all data]

Kanada, Yamamoto, et al., 1991
Kanada, M.; Yamamoto, S.; Saito, S., The microwave spectrum of the ND2 radical, J. Chem. Phys., 1991, 94, 5, 3423, https://doi.org/10.1063/1.460706 . [all data]

Tonooka, Yamamoto, et al., 1997
Tonooka, M.; Yamamoto, S.; Kobayashi, K.; Saito, S., The microwave spectrum of the NH2 radical: The hyperfine structure of the 2B1 ground electronic state, J. Chem. Phys., 1997, 106, 7, 2563, https://doi.org/10.1063/1.473360 . [all data]

Morino and Kawaguchi, 1997
Morino, I.; Kawaguchi, K., Fourier Transform Far-Infrared Spectroscopy of the NH2, NHD, and ND2Radicals, J. Mol. Spectrosc., 1997, 182, 2, 428, https://doi.org/10.1006/jmsp.1996.7221 . [all data]

Ozeki and Saito, 1998
Ozeki, H.; Saito, S., Far-Infrared Laser Sideband Spectroscopy of the NH2Radical, J. Mol. Spectrosc., 1998, 192, 1, 183, https://doi.org/10.1006/jmsp.1998.7678 . [all data]

Muller, Klein, et al., 1999
Muller, H.S.P.; Klein, H.; Belov, S.P.; Winnewisser, G.; Morino, I.; Yamada, K.M.T.; Saito, S., Terahertz Spectroscopy of the Amidogen Radical, NH2, J. Mol. Spectrosc., 1999, 195, 1, 177, https://doi.org/10.1006/jmsp.1999.7820 . [all data]

Petrongolo, Fan, et al., 2003
Petrongolo, C.; Fan, H.; Ionescu, I.; Kuffel, D.; Reid, S.A., Fluorescence spectra of NH[sub 2] X [sup 2]B[sub 1]←A [sup 2]A[sub 1] Σ bands: Experiment and theory, J. Chem. Phys., 2003, 119, 5, 2614, https://doi.org/10.1063/1.1580112 . [all data]

Duxbury and Reid, 2007
Duxbury, G.; Reid, J.P., Renner--Teller interaction, high angular momentum states and spin-orbit interaction in the electronic spectrum of ND, Mol. Phys., 2007, 105, 11-12, 1603, https://doi.org/10.1080/00268970701384480 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH(+) ion,0K	Enthalpy of formation of positive ion at 0K
  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

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