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
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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

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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: 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, NIST Free Links, 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, NIST Free Links, 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

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