Amino radical
- Formula: H2N
- Molecular weight: 16.0226
- IUPAC Standard InChIKey: MDFFNEOEWAXZRQ-UHFFFAOYSA-N
- CAS Registry Number: 13770-40-6
- Chemical structure:
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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 |
---|---|---|---|---|---|
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.
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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 |
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
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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 184.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 177.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
ΔfH°(+) ion | 302.0 ± 1.5 | kcal/mol | N/A | N/A | |
Quantity | Value | Units | Method | Reference | Comment |
ΔfH(+) ion,0K | 302.7 ± 1.5 | kcal/mol | N/A | N/A |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.7710 ± 0.0050 | LPES | Wickham-Jones, Ervin, et al., 1989 | B |
0.766 ± 0.036 | D-EA | MacKay, Hemsworth, et al., 1976 | B |
0.776 ± 0.037 | LPES | Celotta, Bennett, et al., 1974 | B |
0.744 ± 0.022 | LPD | Smyth and Brauman, 1972 | B |
0.760 ± 0.040 | PD | Feldman, 1971 | B |
0.740 ± 0.030 | LPD | Smyth, McIver, et al., 1971 | B |
0.722924 | N/A | Check, Faust, et al., 2001 | HCrO3(t); ; ΔS(EA)=6.6; B |
1.11879 | SI | Page and Goode, 1969 | The Magnetron method, lacking mass analysis, is not considered reliable.; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.78 ± 0.05 | DER | Qi, Sheng, et al., 1995 | LL |
11.14 ± 0.01 | PI | Gibson, Greene, et al., 1985 | LBLHLM |
11.46 ± 0.01 | PE | Dunlavey, Dyke, et al., 1980 | LLK |
11.7 | EI | Melton, 1966 | RDSH |
11.22 | DER | Dibeler, Walker, et al., 1966 | RDSH |
11.4 ± 0.1 | EI | Foner and Hudson, 1958 | RDSH |
12.0 | EI | Locht, Servais, et al., 1988 | Vertical value; LL |
12.00 ± 0.01 | PE | Dunlavey, Dyke, et al., 1980 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
HN+ | 17.440 ± 0.005 | H | PI | Gibson, Greene, et al., 1985 | LBLHLM |
De-protonation reactions
HN- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 397.87 ± 0.48 | kcal/mol | D-EA | Neumark, Lykke, et al., 1985 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 390.99 ± 0.57 | kcal/mol | H-TS | Neumark, Lykke, et al., 1985 | gas phase; B |
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.
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]
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 DO(H2N-H) and DO(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]
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]
Notes
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, 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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