Benzyl radical

• Formula: C₇H₇
• Molecular weight: 91.1305
• IUPAC Standard InChI: InChI=1S/C7H7/c1-7-5-3-2-4-6-7/h2-6H,1H2 Copy

  
• IUPAC Standard InChIKey: SLRMQYXOBQWXCR-UHFFFAOYSA-N Copy
• 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
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • Benzyl-d7 radical
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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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.

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) +  (g)

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

Gas phase ion energetics 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

View reactions leading to C₇H₇⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Vibrational and/or electronic energy levels

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, 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.

Data compiled by: Marilyn E. Jacox

State:   E

State:   D

State:   C

State:   B

State:   A

State:   X

State:   ?

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

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics 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]

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]

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 o-, m-, and p-halobenzyl anions, J. Phys. Chem. A, 1999, 103, 50, 10833-10841, https://doi.org/10.1021/jp992817o . [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Drzaic and Brauman, 1984
Drzaic, P.S.; Brauman, J.I., A determination of the singlet-triplet splitting in phenylnitrene via photoelectron detachment, J. Phys. Chem., 1984, 88, 5285. [all data]

Richardson, Stephenson, et al., 1975
Richardson, J.H.; Stephenson, L.M.; Brauman, J.I., Photodetachment of electrons from large molecular systems: Benzyl anion. An upper Limitlto the electron affinity of C₆H₅CH₂, J. Chem. Phys., 1975, 63, 74. [all data]

Failes, Joyce, et al., 1976
Failes, R.L.; Joyce, J.T.; Walton, E.C., The behaviour of some dimethyl and trimethyl substituted pyridines in the magnetron, J. Phys. D: Appl. Phys., 1976, 9, 1543. [all data]

Page, 1972
Page, F.M., Experimental determination of the electron affinities of inorganic radicals, Adv. Chem. Ser., 1972, 36, 68. [all data]

Page and Goode, 1969
Page, F.M.; Goode, G.C., Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]

Gaines and Page, 1968
Gaines, A.F.; Page, F.M., The Stabilities of Negative Ions.I. The Methyl-, Diphenylmethyl, and Triphenylmethyl Negative Ions, Int. J. Mass Spectrom. Ion Phys., 1968, 1, 4-5, 315, https://doi.org/10.1016/0020-7381(68)85008-9 . [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]

Eiden, Weinhold, et al., 1991
Eiden, G.C.; Weinhold, F.; Weisshar, J.C., Photoelectron spectroscopy of free radicals with cm-1 resolution: The benzyl cation, J. Chem. Phys., 1991, 95, 8665. [all data]

Eiden and Weisshaar, 1991
Eiden, G.C.; Weisshaar, J.C., Adiabatic ionization potential of benzyl radical by two-color resonant two-photon ionization, J. Phys. Chem., 1991, 95, 6194. [all data]

Griller and Lossing, 1981
Griller, D.; Lossing, F.P., On the thermochemistry of α-aminoalkyl radicals, J. Am. Chem. Soc., 1981, 103, 1586. [all data]

Houle and Beauchamp, 1978
Houle, F.A.; Beauchamp, J.L., Detection and investigation of allyl and benzyl radicals by photoelectron spectroscopy, J. Am. Chem. Soc., 1978, 100, 3290. [all data]

Lossing, 1971
Lossing, F.P., Free radicals by mass spectrometry. XLIII. Ionization potentials and ionic heats of formation for vinyl, allyl, and benzyl radicals, Can. J. Chem., 1971, 49, 357. [all data]

Elder and Parr, 1969
Elder, F.A.; Parr, A.C., Photoionization of the cycloheptatrienyl radical, J. Chem. Phys., 1969, 50, 1027. [all data]

Akopyan and Vilesov, 1966
Akopyan, M.E.; Vilesov, F.I., A mass-spectrometric study of the photo-ionisation of benzene derivatives at wavelengths up to 885 A, Zh. Fiz. Khim., 1966, 40, 125, In original 63. [all data]

Harrison, Kebarle, et al., 1961
Harrison, A.G.; Kebarle, P.; Lossing, F.P., Free radicals by mass spectrometry. XXI. The ionization potentials of some meta and para substituted benzyl radicals, J. Am. Chem. Soc., 1961, 83, 777. [all data]

Koenig, Snell, et al., 1976
Koenig, T.; Snell, W.; Chang, J.C., The He(I) photoelectron spectra of benzyl and α-cyanoisopropyl radicals, Tetrahedron Lett., 1976, 50, 4569. [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]

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]

Kim, Wenthold, et al., 1999, 2
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, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  ΔfH(+) ion,0K	Enthalpy of formation of positive ion at 0K
  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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