Amino radical
- Formula: H2N
- Molecular weight: 16.0226
- IUPAC Standard InChIKey: MDFFNEOEWAXZRQ-UHFFFAOYSA-N
- 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. - Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.
Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, Vibrational and/or electronic energy levels, 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 |
---|---|---|---|---|---|
ΔfH°gas | 45.500 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1977 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 46.537 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 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.
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | 298. to 1300. | 1300. to 6000. |
---|---|---|
A | 7.136540 | 8.445261 |
B | 1.462191 | 2.632780 |
C | 2.760459 | -0.280309 |
D | -1.200870 | 0.005407 |
E | 0.021207 | -0.510526 |
F | 43.35691 | 41.62440 |
G | 54.74510 | 54.41011 |
H | 45.50000 | 45.50000 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in June, 1977 | Data last reviewed in June, 1977 |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, 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: 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- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 397.87 ± 0.48 | kcal/mol | D-EA | Neumark, Lykke, et al., 1985 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 390.99 ± 0.57 | kcal/mol | H-TS | Neumark, Lykke, et al., 1985 | gas phase |
Vibrational and/or electronic energy levels
Go To: Top, Gas phase thermochemistry data, Reaction 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 compiled by: Marilyn E. Jacox
State: Ryd
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 98049 | gas | Gibson, Greene, et al., 1985 | |||||
To = 97193 | gas | Gibson, Greene, et al., 1985 | |||||
To = 95753 | gas | Gibson, Greene, et al., 1985 | |||||
To = 93054 | gas | Gibson, Greene, et al., 1985 | |||||
State: A
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 3325 | gas | AB | Dressler and Ramsay, 1959 | |
2 | Bend | 1157.8 | gas | AB EM | Hadj Bachir, Huet, et al., 1999 | ||
State: X
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 1 | Sym. stretch | 3219.37 | gas | LF EM | Kroll, 1975 Vervloet and Merienne-Lafore, 1982 Amano, Bernath, et al., 1982 | |
1 | Sym. stretch | 3219.37 | gas | LD IR | Vervloet, 1988 McKellar, Vervloet, et al., 1990 | ||
1 | Sym. stretch | 3220 | w | N2 | IR | Milligan and Jacox, 1965 | |
2 | Bend | 1497.32 | gas | UV LF | Dressler and Ramsay, 1959 Kroll, 1975 Johns, Ramsay, et al., 1976 Vervloet, Merienne-Lafore, et al., 1978 Hills and McKellar, 1979 | ||
2 | Bend | 1497.32 | gas | LMR IR | Kawaguchi, Yamada, et al., 1980 Burkholder, Howard, et al., 1988 | ||
2 | Bend | 1499 | m | N2 | IR | Milligan and Jacox, 1965 | |
b2 | 3 | Asym. stretch | 3301.11 | gas | LD LF | Amano, Bernath, et al., 1982 Vervloet, 1988 | |
3 | Asym. stretch | 3301.11 | gas | IR | McKellar, Vervloet, et al., 1990 | ||
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
w | Weak |
m | Medium |
o | Energy separation between the v = 0 levels of the excited and electronic ground states. |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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]
Gibson, Greene, et al., 1985
Gibson, S.; Greene, J.; Berkowitz, J.,
Photoionization of the amidogen radical,
J. Chem. Phys., 1985, 83, 4319. [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, Vibrational and/or electronic energy levels, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) 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
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
- Customer support for NIST Standard Reference Data products.