Benzyl radical

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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.

Quantity Value Units Method Reference Comment
Δfgas207. ± 4.kJ/molN/ATsang, 1996 

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: 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) + Benzyl radical (g)

By formula: C12H7MnO5 (g) = C5MnO5 (g) + C7H7 (g)

Quantity Value Units Method Reference Comment
Δr135. ± 19.kJ/molICR/PESMartinho Simões, Schultz, et al., 1985Please 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


Vib. 
sym. 
 No.   Approximate 
 type of mode 
 cm-1   Med.   Method   References

a1 CH stretch 3069 w Ar IR Baskir, Maltsev, et al., 1993
8a CC stretch 1603 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
C-CH2 stretch 1510 ± 25 gas PE Gunion, Gilles, et al., 1992
Kim, Wenthold, et al., 1999
1465 m s gas FE Satink, Meijer, et al., 2003
1469 m Ar IR Baskir, Maltsev, et al., 1993
19a CC stretch 1431 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
19a CC stretch 1423 Ar LF Miller and Andrews, 1981
CH2 deform. 1409 m Ar IR Baskir, Maltsev, et al., 1993
7a 1258 gas EM LF Grajcar and Leach, 1964
Ward, 1968
Selco and Carrick, 1989
Fukushima and Obi, 1990
7a 1264 m Ar IR Baskir, Maltsev, et al., 1993
9a CH deform. 1181 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
18a CH deform. 1046 w m gas EM FE Selco and Carrick, 1989
Satink, Meijer, et al., 2003
1013 m gas FE Satink, Meijer, et al., 2003
1015 w Ar IR Baskir, Maltsev, et al., 1993
1 CC stretch 987.4 gas EM LF Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Cossart-Magos and Leach, 1972
Selco and Carrick, 1989
Fukushima and Obi, 1990
1 CC stretch 982 Ar LF Miller and Andrews, 1981
12a Ring deform. 830 gas EM LF Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
Fukushima and Obi, 1990
6a Ring deform. 524 gas EM LF Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Cossart-Magos and Leach, 1972
Fukushima and Obi, 1990
6a Ring deform. 524 gas PE MPI Gunion, Gilles, et al., 1992
Yao and Bernstein, 1997
Kim, Wenthold, et al., 1999
6a Ring deform. 520 Ar LF Miller and Andrews, 1981
a2 17a CH deform 963 w m gas EM FE Selco and Carrick, 1989
Satink, Meijer, et al., 2003
10a CH deform. 860 gas EM Watmann-Grajcar, 1969
Selco and Carrick, 1989
16a Ring deform. 393 gas EM Watmann-Grajcar, 1969
b1 880 m s gas FE Satink, Meijer, et al., 2003
882.0 w Ar IR Baskir, Maltsev, et al., 1993
762 s gas FE Satink, Meijer, et al., 2003
762.0 vs Ar IR Baskir, Maltsev, et al., 1993
CH2 wag 710.9 w Ar IR Baskir, Maltsev, et al., 1993
667.0 s Ar IR Baskir, Maltsev, et al., 1993
464 w m gas FE Satink, Meijer, et al., 2003
465.0 s Ar IR Baskir, Maltsev, et al., 1993
16b Ring deform. 430 gas EM Watmann-Grajcar, 1969
b2 CH2 a-stretch 3111 w Ar IR Baskir, Maltsev, et al., 1993
8b Ring stretch 1549 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
8b Ring stretch 1530 Ar LF Miller and Andrews, 1981
1444 m s gas FE Satink, Meijer, et al., 2003
1446 m Ar IR Baskir, Maltsev, et al., 1993
1305 w Ar IR Baskir, Maltsev, et al., 1993
9b CH deform. 1152 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
1097 m gas FE Satink, Meijer, et al., 2003
15 CH deform. 1089 gas EM Grajcar and Leach, 1964
Watmann-Grajcar, 1969
948.1 w Ar IR Baskir, Maltsev, et al., 1993
6b Ring deform. 615 gas EM LF Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Cossart-Magos and Leach, 1972
Selco and Carrick, 1989
Fukushima and Obi, 1990
6b Ring deform. 615 gas MPI Yao and Bernstein, 1997
6b Ring deform. 612 Ar LF Miller and Andrews, 1981
18b CH deform. 356 gas EM MPI Grajcar and Leach, 1964
Watmann-Grajcar, 1969
Selco and Carrick, 1989
Fukushima and Obi, 1990
Yao and Bernstein, 1997
18b CH deform. 357 Ar LF Miller and Andrews, 1981

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

wWeak
mMedium
sStrong
vsVery strong
TTentative assignment or approximate value
oEnergy separation between the v = 0 levels of the excited and electronic ground states.
xEnergy 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