CNN Radical
- Formula: CN2
- Molecular weight: 40.0241
- IUPAC Standard InChIKey: QDZARNQKIZUXDK-UHFFFAOYSA-N
- CAS Registry Number: 2468-81-7
- Chemical structure:
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Gas phase thermochemistry data
Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, NIST Free Links, 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 | 139.70 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1966 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 55.380 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1966 |
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 1500. | 1500. to 6000. |
---|---|---|
A | 9.054828 | 14.20631 |
B | 6.152462 | 0.321984 |
C | -2.668691 | -0.055965 |
D | 0.444615 | 0.003432 |
E | -0.049830 | -1.886093 |
F | 136.5822 | 131.8109 |
G | 64.33867 | 68.14579 |
H | 139.7000 | 139.7000 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in June, 1966 | Data last reviewed in June, 1966 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, NIST Free Links, 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
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
1.761 ± 0.010 | LPES | Clifford, Wenthold, et al., 1998 |
Vibrational and/or electronic energy levels
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, NIST Free Links, 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: ?
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
Tx = 51070 | T | N2 | Jacox, 1978 | ||||
State: C
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 48540 ± 50 | Ar | C-X | 206 | 206 | Jacox, 1978 | ||
To = 49100 ± 50 | N2 | C-X | 204 | 204 | Jacox, 1978 | ||
State: B
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 40985 | U | gas | Bise, Hoops, et al., 2000 | ||||
To = 39950 | U | Ar | B-X | 210 | 251 | Jacox, 1978 | |
To = 39850 | U | N2 | B-X | 210 | 251 | Jacox, 1978 | |
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
Σ+ | 1 | Sym. | stretch 1000 T gas PF 2000BIS/HOO4179 | ||||
1 | Sym. | stretch 990 | 40 " Ar AB 1978JAC26 | ||||
1 | Sym. | stretch 990 | 40 " N2 AB 1978JAC26 | ||||
3 | Asym. | stretch 1455 " gas PF 2000BIS/HOO4179 | |||||
3 | Asym. | stretch 1450 | 40 " Ar AB 1978JAC26 | ||||
3 | Asym. | stretch 1450 | 40 " N2 AB 1978JAC26 | ||||
State: A
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 23850 | T | gas | A-X | 395 | 420 | Braun, Bass, et al., 1969 | |
Curtis, Levick, et al., 1988 | |||||||
Bise, Hoops, et al., 2000 | |||||||
To = 23750 | Ne | A-X | 397 | 420 | Weltner and McLeod, 1966 | ||
To = 23830 | Ne | A-X | 397 | 420 | Weltner and McLeod, 1966 | ||
To = 23597 | Ar | A-X | 401 | 424 | Milligan, Jacox, et al., 1965 | ||
Milligan and Jacox, 1966 | |||||||
Bondybey and English, 1977 | |||||||
Wilkerson and Guillory, 1977 | |||||||
To = 23865 | N2 | A-X | 396 | 419 | Milligan, Jacox, et al., 1965 | ||
Milligan and Jacox, 1966 | |||||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
Σ+ | 1 | Sym. | stretch 1386 " gas PF 2000BIS/HOO4179 | ||||
1 | Sym. | stretch 1325 | 10 " Ne AB 1966WEL/MCL3096 | ||||
1 | Sym. | stretch 1322 | 2 " Ar AB | LF 1965MIL/JAC3149 1966MIL/JAC2850 1977 | |||
1 | Sym. | stretch 1335 | 10 " N2 AB 1965MIL/JAC3149 1966MIL/JAC2850 | ||||
Π | 2 | Bend | 525 ± 2 | Ar | LF | Bondybey and English, 1977 | |
Σ+ | 3 | Asym.stretch 1807 | ± | ||||
State: b
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 10690 ± 120 | gas | Clifford, Wenthold, et al., 1998 | |||||
State: a
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 6830 ± 120 | gas | Clifford, Wenthold, et al., 1998 | |||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
Σ+ | 3 | Asym. | stretch 1600 | 120 " gas PE 1998CLI/WEN7100 | |||
State: X
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
Σ+ | 1 | Sym. | stretch 1230 | 120 " gas PE 1998CLI/WEN7100 | |||
1 | Sym. | stretch 1235 " Ne EM 1966WEL/MCL3096 | |||||
1 | Sym. | stretch 1235 " Ar LF 1977BON/ENG664 1992WUR/THO119 | |||||
1 | Sym. | stretch 1241 N | |||||
1 | Sym. | stretch 1252 " N2 IR 1966MIL/JAC2850 1966MOL/THO2684 1971DEK/WEL7106 | |||||
Π | 2 | Bend | 390 ± 120 | gas | PE | Clifford, Wenthold, et al., 1998 | |
2 | Bend | 394 | Ar | LF | Bondybey and English, 1977 | ||
2 | Bend | 393 | Ar | IR | Milligan and Jacox, 1966 | ||
2 | Bend | 394 | N2 | IR | Moll and Thompson, 1966 DeKock and Weltner, 1971 | ||
Σ+ | 3 | Asym. | stretch 1425 | 120 " gas PE 1998CLI/WEN7100 | |||
3 | Asym.stretch 1419 " Ar LF 1992WUR/THO119 | ||||||
Additional references: Jacox, 1994, page 71; Jacox, 2003, page 114; Wasserman, Barash, et al., 1965
Notes
U | Upper bound |
T | Tentative assignment or approximate value |
o | Energy separation between the v = 0 levels of the excited and electronic ground states. |
x | Energy separation between the band maximum of the excited electronic state and the v = 0 level of the ground state. |
References
Go To: Top, Gas phase 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]
Clifford, Wenthold, et al., 1998
Clifford, E.P.; Wenthold, P.G.; Lineberger, W.C.; Peterssom, G.A.; Broaddus, K.M.; Kass, S.R.; Kato, S.,
Properties of Diazocarbene [CNN] and the diazomethyl Radical [HCNN] via Ion Chemistry and Spectroscopy,
J. Phys. Chem. A, 1998, 102, 36, 7100, https://doi.org/10.1021/jp9802735
. [all data]
Jacox, 1978
Jacox, M.E.,
Matrix isolation study of the reaction of carbon atoms with molecular nitrogen,
J. Mol. Spectrosc., 1978, 72, 1, 26, https://doi.org/10.1016/0022-2852(78)90040-1
. [all data]
Bise, Hoops, et al., 2000
Bise, R.T.; Hoops, A.A.; Choi, H.; Neumark, D.M.,
Photodissociation dynamics of the CNN free radical,
J. Chem. Phys., 2000, 113, 10, 4179, https://doi.org/10.1063/1.1288267
. [all data]
Braun, Bass, et al., 1969
Braun, W.; Bass, A.M.; Davis, D.D.; Simmons, J.D.,
Flash Photolysis of Carbon Suboxide: Absolute Rate Constants for Reactions of C(FormulaP) and C(Formula) with HFormula, NFormula, CO, NO, OFormula and CHFormula,
Proc. Roy. Soc. (London) A312, 1969, 312, 1510, 417, https://doi.org/10.1098/rspa.1969.0168
. [all data]
Curtis, Levick, et al., 1988
Curtis, M.C.; Levick, A.P.; Sarre, P.J.,
Laser-Induced-Fluorescence Spectrum of the CNN Molecule,
Laser Chem., 1988, 9, 4-6, 359, https://doi.org/10.1155/LC.9.359
. [all data]
Weltner and McLeod, 1966
Weltner, W., Jr.; McLeod, D., Jr.,
Spectroscopy of Carbon Vapor Condensed in Rare-Gas Matrices at 4°K. III,
J. Chem. Phys., 1966, 45, 8, 3096, https://doi.org/10.1063/1.1728066
. [all data]
Milligan, Jacox, et al., 1965
Milligan, D.E.; Jacox, M.E.; Bass, A.M.,
Matrix Isolation Study of the Photolysis of Cyanogen Azide. The Infrared and Ultraviolet Spectra of the Free Radical NCN,
J. Chem. Phys., 1965, 43, 9, 3149, https://doi.org/10.1063/1.1697289
. [all data]
Milligan and Jacox, 1966
Milligan, D.E.; Jacox, M.E.,
Matrix-Isolation Study of the Infrared and Ultraviolet Spectra of the Free Radical CNN,
J. Chem. Phys., 1966, 44, 8, 2850, https://doi.org/10.1063/1.1727144
. [all data]
Bondybey and English, 1977
Bondybey, V.E.; English, J.H.,
Spectroscopy and vibrational relaxation of CNN in rare gas solids,
J. Chem. Phys., 1977, 67, 2, 664, https://doi.org/10.1063/1.434869
. [all data]
Wilkerson and Guillory, 1977
Wilkerson, J.L.; Guillory, W.A.,
Laser-induced temporal and wavelength resolved spectroscopy of the 3Π-3Σ- system of matrix-isolated CNN,
J. Mol. Spectrosc., 1977, 66, 2, 188, https://doi.org/10.1016/0022-2852(77)90209-0
. [all data]
Moll and Thompson, 1966
Moll, N.G.; Thompson, W.E.,
Reactions of Carbon Atoms with N2, H2, and D2 at 4.2°K,
J. Chem. Phys., 1966, 44, 7, 2684, https://doi.org/10.1063/1.1727111
. [all data]
DeKock and Weltner, 1971
DeKock, R.L.; Weltner, W., Jr.,
C2O, CN2, and C3O molecules,
J. Am. Chem. Soc., 1971, 93, 25, 7106, https://doi.org/10.1021/ja00754a081
. [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, 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]
Wasserman, Barash, et al., 1965
Wasserman, E.; Barash, L.; Yager, W.A.,
None,
J. Am. Chem. Soc., 1965, 87, 9, 2075, https://doi.org/10.1021/ja01087a058
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, NIST Free Links, References
- Symbols used in this document:
EA Electron affinity S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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