Benzyl radical
- Formula: C7H7
- Molecular weight: 91.1305
- IUPAC Standard InChIKey: SLRMQYXOBQWXCR-UHFFFAOYSA-N
- CAS Registry Number: 2154-56-5
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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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 | 207. ± 4. | kJ/mol | N/A | Tsang, 1996 |
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: José A. Martinho Simões
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
C12H7MnO5 (g) = C5MnO5 (g) + (g)
By formula: C12H7MnO5 (g) = C5MnO5 (g) + C7H7 (g)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 135. ± 19. | kJ/mol | ICR/PES | Martinho Simões, Schultz, et al., 1985 | Please also see Martinho Simões and Beauchamp, 1990. The reaction enthalpy was derived from the appearance energy of Mn(CO)5(+), 830. ± 19. kJ/mol, using Mn(CO)5(Bz) as the neutral precursor, together with the adiabatic ionization energy of Bz radical, 694.7 ± 1.9 kJ/mol Martinho Simões, Schultz, et al., 1985. The enthalpy of formation relies on -642.5 ± 9.4 kJ/mol for the enthalpy of formation of Mn(CO)5(Bz)(g) |
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: E
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
Tx = 43500 | T | gas | E-X | Bayrakciken and Nicholas, 1970 | |||
State: D
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
Tx = 39200 | gas | D-X | 245 | 260 | Bayrakciken and Nicholas, 1970 | ||
Hoffbauer and Hudgens, 1985 | |||||||
Tx = 40800 | Ne | D-X | Angell, Hedaya, et al., 1967 | ||||
State: C
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 32760 | gas | C-X | 291 | 309 | Porter and Wright, 1955 | ||
Grajcar and Leach, 1964 | |||||||
Ward, 1968 | |||||||
To = 32730 | Ne | C-X | Angell, Hedaya, et al., 1967 | ||||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
a1 | 7a | C-CH2 stretch | 1145 | gas | AB | Ward, 1968 | |
18a | CH deform. | 968 | gas | AB | Ward, 1968 | ||
1 | Ring breathing | 931 | gas | AB | Ward, 1968 | ||
12a | Ring deform. | 804 | gas | AB | Ward, 1968 | ||
6a | Ring deform. | 432 | gas | AB | Ward, 1968 | ||
b2 | 6b | Ring deform. | 525 | gas | AB | Ward, 1968 | |
18b | CH deform. | 276 | gas | AB | Ward, 1968 | ||
State: B
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 22850 | T | gas | Cossart-Magos and Leach, 1976 | ||||
Fukushima and Obi, 1992 | |||||||
Lin, Tan, et al., 1992 | |||||||
Eiden and Weisshaar, 1996 | |||||||
Yao and Bernstein, 1997 | |||||||
State: A
Energy (cm-1) |
Med. | Transition | λmin (nm) |
λmax (nm) |
References | ||
---|---|---|---|---|---|---|---|
To = 22001.5 | gas | A-X | 429 | 471 | Schuler, Reinebeck, et al., 1952 | ||
Schuler and Michel, 1955 | |||||||
Porter and Ward, 1964 | |||||||
Grajcar and Leach, 1964 | |||||||
Cossart-Magos and Leach, 1972 | |||||||
Brenner, Smith, et al., 1976 | |||||||
Fukushima and Obi, 1990 | |||||||
Im and Bernstein, 1991 | |||||||
Fukushima and Obi, 1992 | |||||||
Fukushima and Obi, 1995 | |||||||
Yao and Bernstein, 1997 | |||||||
Tonokura and Koshi, 2003 | |||||||
To = 22003 | Ne | A-X | 429 | 455 | Angell, Hedaya, et al., 1967 | ||
To = 21862 | Ar | A-X | 430 | 510 | Miller and Andrews, 1981 | ||
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
910 | Ar | LF | Miller and Andrews, 1981 | ||||
770 | T | gas | LF | Fukushima and Obi, 1990 | |||
798 | Ar | LF | Miller and Andrews, 1981 | ||||
6a | Ring deform. | 437 | gas | AB LF | Cossart-Magos and Leach, 1976 Selco and Carrick, 1989 Fukushima and Obi, 1990 Fukushima and Obi, 1992 | ||
6a | Ring deform. | 433 | Ne | AB | Angell, Hedaya, et al., 1967 | ||
6a | Ring deform. | 456 | Ar | LF | Miller and Andrews, 1981 | ||
388 | gas | AB | Cossart-Magos and Leach, 1976 Cossart-Magos and Goetz, 1986 Selco and Carrick, 1989 Fukushima and Obi, 1992 | ||||
402 | Ne | AB | Angell, Hedaya, et al., 1967 | ||||
328 | gas | AB | Cossart-Magos and Leach, 1976 Cossart-Magos and Goetz, 1986 Selco and Carrick, 1989 Fukushima and Obi, 1992 | ||||
344 | Ne | AB | Angell, Hedaya, et al., 1967 | ||||
State: X
State: ?
Vib. sym. |
No. | Approximate type of mode |
cm-1 | Med. | Method | References | |
---|---|---|---|---|---|---|---|
b1 | 666 | vs | gas | FE | Satink, Meijer, et al., 2003 | ||
Additional references: Jacox, 1994, page 392; Jacox, 1998, page 349; Jacox, 2003, page 372; Okamura, Charlton, et al., 1982; Reisler, Pessine, et al., 1983; Carrick and Selco, 1990
Notes
w | Weak |
m | Medium |
s | Strong |
vs | Very strong |
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, 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.
Tsang, 1996
Tsang, W.,
Heats of Formation of Organic Free Radicals by Kinetic Methods
in Energetics of Organic Free Radicals, Martinho Simoes, J.A.; Greenberg, A.; Liebman, J.F., eds., Blackie Academic and Professional, London, 1996, 22-58. [all data]
Martinho Simões, Schultz, et al., 1985
Martinho Simões, J.A.; Schultz, J.C.; Beauchamp, J.L.,
Organometallics, 1985, 4, 1238. [all data]
Martinho Simões and Beauchamp, 1990
Martinho Simões, J.A.; Beauchamp, J.L.,
Chem. Rev., 1990, 90, 629. [all data]
Bayrakciken and Nicholas, 1970
Bayrakciken, F.; Nicholas, J.E.,
J. Chem. Soc. B, 1970, 691. [all data]
Hoffbauer and Hudgens, 1985
Hoffbauer, M.A.; Hudgens, J.W.,
Multiphoton ionization detection of gas-phase benzyl radicals,
J. Phys. Chem., 1985, 89, 24, 5152, https://doi.org/10.1021/j100270a005
. [all data]
Angell, Hedaya, et al., 1967
Angell, C.L.; Hedaya, E.; McLeod, D., Jr.,
None,
J. Am. Chem. Soc., 1967, 89, 16, 4214, https://doi.org/10.1021/ja00992a042
. [all data]
Porter and Wright, 1955
Porter, G.; Wright, F.J.,
Primary photochemical processes in aromatic molecules. Part 3. Absorption spectra of benzyl, anilino, phenoxy and related free radicals,
Trans. Faraday Soc., 1955, 51, 1469, https://doi.org/10.1039/tf9555101469
. [all data]
Grajcar and Leach, 1964
Grajcar, L.; Leach, S.,
J. Chim. Phys., 1964, 61, 1523. [all data]
Ward, 1968
Ward, B.,
Spectrochim. Acta, 1968, 24A, 813. [all data]
Cossart-Magos and Leach, 1976
Cossart-Magos, C.; Leach, S.,
Two-mode vibronic interaction between neighboring 1 2A2 and 2 2B2 excited electronic states of the benzyl radical,
J. Chem. Phys., 1976, 64, 10, 4006, https://doi.org/10.1063/1.432034
. [all data]
Fukushima and Obi, 1992
Fukushima, M.; Obi, K.,
Jet spectroscopy of benzyl and benzyl-α-d2,
J. Chem. Phys., 1992, 96, 6, 4224, https://doi.org/10.1063/1.462815
. [all data]
Lin, Tan, et al., 1992
Lin, T.-Y.D.; Tan, X.-Q.; Cerny, T.M.; Williamson, J.M.; Cullin, D.W.; Miller, T.A.,
High-resolution fluorescence excitation spectra of jet-cooled benzyl and p-methylbenzyl radicals,
Chem. Phys., 1992, 167, 1-2, 203, https://doi.org/10.1016/0301-0104(92)80035-T
. [all data]
Eiden and Weisshaar, 1996
Eiden, G.C.; Weisshaar, J.C.,
Vibronic coupling mechanism in the A 2A2--B 2B2 excited states of benzyl radical,
J. Chem. Phys., 1996, 104, 22, 8896, https://doi.org/10.1063/1.471659
. [all data]
Yao and Bernstein, 1997
Yao, J.; Bernstein, E.R.,
On the formation and vibronic spectroscopy of α-halobenzyl radicals in a supersonic expansion,
J. Chem. Phys., 1997, 107, 9, 3352, https://doi.org/10.1063/1.474710
. [all data]
Schuler, Reinebeck, et al., 1952
Schuler, H.; Reinebeck, L.; Koberle, R.,
Z. Naturforsch., 1952, 7a, 421, 428. [all data]
Schuler and Michel, 1955
Schuler, H.; Michel, A.,
Z. Naturforsch., 1955, 10a, 459. [all data]
Porter and Ward, 1964
Porter, G.; Ward, B.,
J. Chim. Phys., 1964, 61, 1517. [all data]
Cossart-Magos and Leach, 1972
Cossart-Magos, C.; Leach, S.,
Determination of the Symmetry of the First Excited Electronic State of Benzyl by Rotational Contour Analysis of Vibronic Bands of the Emission Spectra of C6H5CH2, C6H5CD2, and C6D5CD2,
J. Chem. Phys., 1972, 56, 4, 1534, https://doi.org/10.1063/1.1677403
. [all data]
Brenner, Smith, et al., 1976
Brenner, D.M.; Smith, G.P.; Zare, R.N.,
Rearrangement of the o-tolyl radical to the benzyl radical at zero pressure,
J. Am. Chem. Soc., 1976, 98, 21, 6707, https://doi.org/10.1021/ja00437a052
. [all data]
Fukushima and Obi, 1990
Fukushima, M.; Obi, K.,
Jet spectroscopy and excited state dynamics of benzyl and substituted benzyl radicals,
J. Chem. Phys., 1990, 93, 12, 8488, https://doi.org/10.1063/1.459710
. [all data]
Im and Bernstein, 1991
Im, H.S.; Bernstein, E.R.,
Mass resolved excitation spectroscopy of radicals: benzyl and phenylnitrene,
J. Chem. Phys., 1991, 95, 6326. [all data]
Fukushima and Obi, 1995
Fukushima, M.; Obi, K.,
Dispersed fluorescence spectra from single vibronic levels of the benzyl radical observed in a pulsed discharge jet,
Chem. Phys. Lett., 1995, 242, 4-5, 443, https://doi.org/10.1016/0009-2614(95)00779-4
. [all data]
Tonokura and Koshi, 2003
Tonokura, K.; Koshi, M.,
Cavity Ring-Down Spectroscopy of the Benzyl Radical,
J. Phys. Chem. A, 2003, 107, 22, 4457, https://doi.org/10.1021/jp027280k
. [all data]
Miller and Andrews, 1981
Miller, J.H.; Andrews, L.,
Emission and excitation spectra of benzyl radicals in solid argon,
J. Mol. Spect., 1981, 90, 1, 20, https://doi.org/10.1016/0022-2852(81)90328-3
. [all data]
Selco and Carrick, 1989
Selco, J.J.; Carrick, P.G.,
Jet cooled emission spectra of toluene and the benzyl radical,
J. Mol. Spectrosc., 1989, 137, 1, 13, https://doi.org/10.1016/0022-2852(89)90264-6
. [all data]
Cossart-Magos and Goetz, 1986
Cossart-Magos, C.; Goetz, W.,
Rotational contour analysis of selected absorption bands of benzyl produced by flash photolysis,
J. Mol. Spectrosc., 1986, 115, 2, 366, https://doi.org/10.1016/0022-2852(86)90053-6
. [all data]
Baskir, Maltsev, et al., 1993
Baskir, E.G.; Maltsev, A.K.; Korolev, V.A.; Khabashesku, V.N.; Nefedov, O.M.,
Izv. Akad. Nauk, 1993, Ser. Khim., 1499. [all data]
Watmann-Grajcar, 1969
Watmann-Grajcar, L.,
J. Chim. Phys., 1969, 66, 1023. [all data]
Gunion, Gilles, et al., 1992
Gunion, R.F.; Gilles, M.K.; Polak, M.L.; Lineberger, W.C.,
Ultraviolet Photoelectron Spectroscopy of the Phenide, Benzyl, and Phenoxide Anions.,
Int. J. Mass Spectrom. Ion Proc., 1992, 117, 601, https://doi.org/10.1016/0168-1176(92)80115-H
. [all data]
Kim, Wenthold, et al., 1999
Kim, J.B.; Wenthold, P.G.; Lineberger, W.C.,
Ultraviolet Photoelectron Spectroscopy of,
J. Phys. Chem. A, 1999, 103, 50, 10833, https://doi.org/10.1021/jp992817o
. [all data]
Satink, Meijer, et al., 2003
Satink, R.G.; Meijer, G.; von Helden, G.,
Infrared Spectroscopy of Neutral C,
J. Am. Chem. Soc., 2003, 125, 51, 15714, https://doi.org/10.1021/ja038329i
. [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]
Okamura, Charlton, et al., 1982
Okamura, T.; Charlton, T.R.; Thrush, B.A.,
Laser-induced fluorescence of benzyl radicals in the gas phase,
Chem. Phys. Lett., 1982, 88, 4, 369, https://doi.org/10.1016/0009-2614(82)83027-3
. [all data]
Reisler, Pessine, et al., 1983
Reisler, H.; Pessine, F.B.T.; Wittig, C.,
Time resolved observations of NH2 and benzyl radicals produced in the infrared multiple photon dissociation of benzylamine,
Chem. Phys. Lett., 1983, 99, 5-6, 388, https://doi.org/10.1016/0009-2614(83)80160-2
. [all data]
Carrick and Selco, 1990
Carrick, P.G.; Selco, J.J.,
Low temperature rotational band contours of vibronic transitions of the benzyl radical,
J. Mol. Spectrosc., 1990, 139, 2, 449, https://doi.org/10.1016/0022-2852(90)90081-Z
. [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:
ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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