Hydroperoxy radical

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Gas phase ion energetics data

Go To: Top, 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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 HO2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)11.35 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)158.kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity150.0kcal/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
1.0780 ± 0.0060LPESRamond, Blanksby, et al., 2002Give dfH(HOO.) = 3.2±2.1 kcal/mol; B
1.0760 ± 0.0060LPESClifford, Wenthold, et al., 1998Revised per G.B. Ellison, due to improper rotational correction in lit value: 1.084±0.006; B
1.078 ± 0.017LPESOakes, Harding, et al., 1985B
1.105 ± 0.091D-EABierbaum, Schmidt, et al., 1981value altered from reference due to change in acidity scale; B
1.88 ± 0.11TherBenson and Nangia, 1980From a solution phase thermodynamic cycle; B

Ionization energy determinations

IE (eV) Method Reference Comment
11.35 ± 0.01PEDyke, Jonathan, et al., 1981LLK
11.67 ± 0.15EITal'roze, Butkovskaya, et al., 1978LLK
11.53 ± 0.02EIFoner and Hudson, 1955RDSH
11.54PEDyke, Jonathan, et al., 1981Vertical value; LLK

De-protonation reactions

Oxygen anion + Hydrogen cation = Hydroperoxy radical

By formula: O2- + H+ = HO2

Quantity Value Units Method Reference Comment
Δr352.99 ± 0.72kcal/molD-EATravers, Cowles, et al., 1989gas phase; B
Quantity Value Units Method Reference Comment
Δr346.67 ± 0.82kcal/molH-TSTravers, Cowles, et al., 1989gas phase; B

Vibrational and/or electronic energy levels

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.

Data compiled by: Marilyn E. Jacox

State:   B


 Energy 
 (cm-1
 Med.   Transition   λmin 
 (nm) 
 λmax 
 (nm) 
 References

Tx = 48800 gas B-X 200 280 Troe, 1969
Kijewski and Troe, 1971
Paukert and Johnston, 1972
Hochanadel, Ghormley, et al., 1972
Crowley, Simon, et al., 1991

State:   A


 Energy 
 (cm-1
 Med.   Transition   λmin 
 (nm) 
 λmax 
 (nm) 
 References

To = 7029.688 gas A-X 1130 2120 Hunziker and Wendt, 1974
Becker, Fink, et al., 1974
Hunziker and Wendt, 1976
Freedman and Jones, 1976
Becker, Fink, et al., 1978
Tuckett, Freedman, et al., 1979
Fink, Kruse, et al.
Fink and Ramsay, 1997
Ramond, Blanksby, et al., 2002, 2


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

a' 1 OH stretch 3268.5 gas EM Fink, Kruse, et al.
2 Bend 1285 gas EM Fink, Kruse, et al.
3 OO stretch 929.068 gas AB EM Hunziker and Wendt, 1976
Becker, Fink, et al., 1978
Holstein, Fink, et al., 1983
Fink, Kruse, et al.
3 OO stretch 929.068 gas PE Ramond, Blanksby, et al., 2002, 2

State:   X


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

a' 1 OH stretch 3436.20 gas LD Yamada, Endo, et al., 1983
1 OH stretch 3415.1 Ne IR Thompson and Jacox, 1989
Jacox and Thompson
1 OH stretch 3412.5 s Ar IR Milligan and Jacox, 1963
Jacox and Milligan, 1972
Smith and Andrews, 1974
1 OH stretch 3400 O2 IR Bandow and Akimoto, 1985
2 Bend 1391.75 gas DL IR Nagai, Endo, et al., 1981
Burkholder, Hammer, et al., 1992
2 Bend 1397.8 Ne IR Thompson and Jacox, 1989
Jacox and Thompson
2 Bend 1388.5 vs Ar IR Milligan and Jacox, 1963
Jacox and Milligan, 1972
Smith and Andrews, 1974
2 Bend 1392 O2 IR Bandow and Akimoto, 1985
3 OO stretch 1097.63 gas LMR DL Johns, McKellar, et al., 1978
Buchanan, Thrush, et al., 1983
Zahniser and Stanton, 1984
Nelson and Zahniser, 1991
3 OO stretch 1097.63 gas IR PE Burkholder, Hammer, et al., 1992
Ramond, Blanksby, et al., 2002, 2
3 OO stretch 1100.3 Ne IR Thompson and Jacox, 1989
Jacox and Thompson
3 OO stretch 1101.1 s Ar IR Milligan and Jacox, 1963
Jacox and Milligan, 1972
Smith and Andrews, 1974
3 OO stretch 1109 O2 IR Bandow and Akimoto, 1985

Additional references: Jacox, 1994, page 49; Jacox, 1998, page 153; Jacox, 2003, page 43; Radford, Evenson, et al., 1974; Hougen, 1975; Hougen, Radford, et al., 1975; Beers and Howard, 1975; Beers and Howard, 1976; Saito, 1977; Tuckett, Freedman, et al., 1979, 2; McKellar, 1979; Barnes, Brown, et al., 1980; Charo and De Lucia, 1982; Saito, Endo, et al., 1983; Lubic, Amano, et al., 1984; Uehara, Kawaguchi, et al., 1985; Sears, Takacs, et al., 1986; Chance, Park, et al., 1995; Chance, Ramsay, et al., 2001; Fink and Ramsay, 2002; DeSain, Ho, et al., 2003; Wang and Andrews, 2005; Fink and Ramsay, 2006

Notes

sStrong
vsVery strong
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 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.

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]

Ramond, Blanksby, et al., 2002
Ramond, T.M.; Blanksby, S.J.; Kato, S.; Bierbaum, V.M.; Davico, G.E.; Schwartz, R.L.; Lineberger, W.C.; Elliso, Heat of formation of the hydroperoxyl radical HOO via negative ion studies, J. Phys. Chem. A, 2002, 106, 42, 9641-9647, https://doi.org/10.1021/jp014614h . [all data]

Clifford, Wenthold, et al., 1998
Clifford, E.P.; Wenthold, P.G.; Gareyev, R.; Lineberger, W.C.; DePuy, C.H.; Bierbaum, V.M.; Ellison, G.B., Photoelectron spectroscopy, gas phase acidity, and thermochemistry of tert-butyl hydroperoxide: Mechanisms for the rearrangement of peroxyl radicals, J. Chem. Phys., 1998, 109, 23, 10293-10310, https://doi.org/10.1063/1.477725 . [all data]

Oakes, Harding, et al., 1985
Oakes, J.M.; Harding, L.B.; Ellison, G.B., The photoelectron spectroscopy of HO2-, J. Chem. Phys., 1985, 83, 5400. [all data]

Bierbaum, Schmidt, et al., 1981
Bierbaum, V.M.; Schmidt, R.J.; DePuy, C.H.; Mead, R.H.; Schulz, P.A.; Lineberger, W.C., Reactions of carbanions with triplet and singlet molecular oxygen, J. Am. Chem. Soc., 1981, 103, 6262. [all data]

Benson and Nangia, 1980
Benson, S.W.; Nangia, P.S., Electron affinity of HO2. and HOx radicals, J. Am. Chem. Soc., 1980, 102, 2843. [all data]

Dyke, Jonathan, et al., 1981
Dyke, J.M.; Jonathan, N.B.H.; Morris, A.; Winter, M., Vacuum ultraviolet photoelectron spectroscopy of transient species. Part 13. Observation of the X3A state of HO2, Mol. Phys., 1981, 44, 1059. [all data]

Tal'roze, Butkovskaya, et al., 1978
Tal'roze, V.L.; Butkovskaya, N.I.; Larichev, M.N.; Leipunskii, I.O.; Morozov, I.I.; Dodonov, A.F.; Kudrov, B.V.; Zelenov, V.V.; Raznikov, V.V., Advances in the mass spectrometry of free radicals, Adv. Mass Spectrom., 1978, 7, 693. [all data]

Foner and Hudson, 1955
Foner, S.N.; Hudson, R.L., Ionization potential of the free HO2 radical and the H-O2 bond dissociation energy, J. Chem. Phys., 1955, 23, 1364. [all data]

Travers, Cowles, et al., 1989
Travers, M.J.; Cowles, D.C.; Ellison, G.B., Reinvestigation of the Electron Affinities of O2 and NO, Chem. Phys. Lett., 1989, 164, 5, 449, https://doi.org/10.1016/0009-2614(89)85237-6 . [all data]

Troe, 1969
Troe, J., Ber. Bunsenges. Phys. Chem., 1969, 73, 946. [all data]

Kijewski and Troe, 1971
Kijewski, H.; Troe, J., Study of the pyrolysis of H2O2 in the presence of H2and CO by use of UV absorption of HO2, Int. J. Chem. Kinet., 1971, 3, 3, 223, https://doi.org/10.1002/kin.550030304 . [all data]

Paukert and Johnston, 1972
Paukert, T.T.; Johnston, H.S., Spectra and Kinetics of the Hydroperoxyl Free Radical in the Gas Phase, J. Chem. Phys., 1972, 56, 6, 2824, https://doi.org/10.1063/1.1677613 . [all data]

Hochanadel, Ghormley, et al., 1972
Hochanadel, C.J.; Ghormley, J.A.; Ogren, P.J., Absorption Spectrum and Reaction Kinetics of the HO2 Radical in the Gas Phase, J. Chem. Phys., 1972, 56, 9, 4426, https://doi.org/10.1063/1.1677885 . [all data]

Crowley, Simon, et al., 1991
Crowley, J.N.; Simon, F.G.; Burrows, J.P.; Moortgat, G.K.; Jenkin, M.E.; Cox, R.A., The HO2 radical UV absorption spectrum measured by molecular modulation, UV/diode-array spectroscopy, J. Photochem. Photobiol. A: Chem., 1991, 60, 1, 1, https://doi.org/10.1016/1010-6030(91)90001-A . [all data]

Hunziker and Wendt, 1974
Hunziker, H.E.; Wendt, H.R., Near infrared absorption spectrum of HO2, J. Chem. Phys., 1974, 60, 11, 4622, https://doi.org/10.1063/1.1680949 . [all data]

Becker, Fink, et al., 1974
Becker, K.H.; Fink, E.H.; Langen, P.; Schurath, U., Near infrared emission bands of the HO2 radical, J. Chem. Phys., 1974, 60, 11, 4623, https://doi.org/10.1063/1.1680950 . [all data]

Hunziker and Wendt, 1976
Hunziker, H.E.; Wendt, H.R., Electronic absorption spectra of organic peroxyl radicals in the near infrared, J. Chem. Phys., 1976, 64, 8, 3488, https://doi.org/10.1063/1.432606 . [all data]

Freedman and Jones, 1976
Freedman, P.A.; Jones, W.J., J. Chem. Soc., 1976, Faraday Trans. 2 72, 207. [all data]

Becker, Fink, et al., 1978
Becker, K.H.; Fink, E.H.; Leiss, A.; Schurath, U., A study of the near infrared emission bands of the hydroperoxyl radical at medium resolution, Chem. Phys. Lett., 1978, 54, 1, 191, https://doi.org/10.1016/0009-2614(78)85694-2 . [all data]

Tuckett, Freedman, et al., 1979
Tuckett, R.P.; Freedman, P.A.; Jones, W.J., The emission bands of HO, Mol. Phys., 1979, 37, 2, 379, https://doi.org/10.1080/00268977900100331 . [all data]

Fink, Kruse, et al.
Fink, E.H.; Kruse, H.; Ramsay, D.A., Paper WF2, 42nd Symposium on Molecular Spectroscopy, Columbus, Ohio, June 1987.. [all data]

Fink and Ramsay, 1997
Fink, E.H.; Ramsay, D.A., High-Resolution Study of theÃ2A´ → X2A´´ Transition of HO2: Analysis of the 000--000 Band, J. Mol. Spectrosc., 1997, 185, 2, 304, https://doi.org/10.1006/jmsp.1997.7401 . [all data]

Ramond, Blanksby, et al., 2002, 2
Ramond, R.M.; Blanksby, S.J.; Kato, S.; Bierbaum, V.M.; Davico, G.E.; Schwartz, R.L.; Lineberger, W.C.; Ellison, G.B., Heat of Formation of the Hydroperoxyl Radical HOO Via Negative Ion Studies, J. Phys. Chem. A, 2002, 106, 42, 9641, https://doi.org/10.1021/jp014614h . [all data]

Holstein, Fink, et al., 1983
Holstein, K.J.; Fink, E.H.; Zabel, F., The ν3 vibration of electronically excited HO2(A2A´), J. Mol. Spectrosc., 1983, 99, 1, 231, https://doi.org/10.1016/0022-2852(83)90307-7 . [all data]

Yamada, Endo, et al., 1983
Yamada, C.; Endo, Y.; Hirota, E., Difference frequency laser spectroscopy of the ν1 band of the HO2 radical, J. Chem. Phys., 1983, 78, 7, 4379, https://doi.org/10.1063/1.445321 . [all data]

Thompson and Jacox, 1989
Thompson, W.E.; Jacox, M.E., The vibrational spectra of molecular ions isolated in solid neon. II. O+4 and O-4, J. Chem. Phys., 1989, 91, 7, 3826, https://doi.org/10.1063/1.456868 . [all data]

Jacox and Thompson
Jacox, M.E.; Thompson, W.E., J. Phys. Chem. A 117. [all data]

Milligan and Jacox, 1963
Milligan, D.E.; Jacox, M.E., Infrared Spectroscopic Evidence for the Species HO2, J. Chem. Phys., 1963, 38, 11, 2627, https://doi.org/10.1063/1.1733562 . [all data]

Jacox and Milligan, 1972
Jacox, M.E.; Milligan, D.E., Spectrum and structure of the HO2 free radical, J. Mol. Spectrosc., 1972, 42, 3, 495, https://doi.org/10.1016/0022-2852(72)90225-1 . [all data]

Smith and Andrews, 1974
Smith, D.W.; Andrews, L., Argon matrix infrared spectra and vibrational analysis of the hydroperoxyl and deuteroperoxyl free radicals, J. Chem. Phys., 1974, 60, 1, 81, https://doi.org/10.1063/1.1680809 . [all data]

Bandow and Akimoto, 1985
Bandow, H.; Akimoto, H., Photochemistry of ketene in oxygen/argon matrixes and in solid oxygen at 11 K, J. Phys. Chem., 1985, 89, 5, 845, https://doi.org/10.1021/j100251a026 . [all data]

Nagai, Endo, et al., 1981
Nagai, K.; Endo, Y.; Hirota, E., Diode laser spectroscopy of the HO2 ν2 band, J. Mol. Spectrosc., 1981, 89, 2, 520, https://doi.org/10.1016/0022-2852(81)90044-8 . [all data]

Burkholder, Hammer, et al., 1992
Burkholder, J.B.; Hammer, P.D.; Howard, C.J.; Towle, J.P.; Brown, J.M., Fourier transform spectroscopy of the ν2 and ν3 bands of HO2, J. Mol. Spectrosc., 1992, 151, 2, 493, https://doi.org/10.1016/0022-2852(92)90582-9 . [all data]

Johns, McKellar, et al., 1978
Johns, J.W.C.; McKellar, A.R.W.; Riggin, M., Laser magnetic resonance spectroscopy of the ν3 fundamental band of HO2 at 9.1 μm, J. Chem. Phys., 1978, 68, 9, 3957, https://doi.org/10.1063/1.436308 . [all data]

Buchanan, Thrush, et al., 1983
Buchanan, J.W.; Thrush, B.A.; Tyndall, G.S., The absolute intensity of the ν3 band of HO2, Chem. Phys. Lett., 1983, 103, 2, 167, https://doi.org/10.1016/0009-2614(83)87487-9 . [all data]

Zahniser and Stanton, 1984
Zahniser, M.S.; Stanton, A.C., A measurement of the vibrational band strength for the ν3 band of the HO2 radical, J. Chem. Phys., 1984, 80, 10, 4951, https://doi.org/10.1063/1.446517 . [all data]

Nelson and Zahniser, 1991
Nelson, D.D., Jr.; Zahniser, M.S., Diode laser spectroscopy of the ν3 vibration of the HO2 radical, J. Mol. Spectrosc., 1991, 150, 2, 527, https://doi.org/10.1016/0022-2852(91)90247-8 . [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]

Radford, Evenson, et al., 1974
Radford, H.E.; Evenson, K.M.; Howard, C.J., HO2 detected by laser magnetic resonance, J. Chem. Phys., 1974, 60, 8, 3178, https://doi.org/10.1063/1.1681503 . [all data]

Hougen, 1975
Hougen, J.T., The assignment of molecular infrared spectra from a laser magnetic resonance spectrometer, J. Mol. Spectrosc., 1975, 54, 3, 447, https://doi.org/10.1016/0022-2852(75)90172-1 . [all data]

Hougen, Radford, et al., 1975
Hougen, J.T.; Radford, H.E.; Evenson, K.M.; Howard, C.J., Analysis of the laser magnetic resonance spectrum of HO2, J. Mol. Spectrosc., 1975, 56, 2, 210, https://doi.org/10.1016/0022-2852(75)90236-2 . [all data]

Beers and Howard, 1975
Beers, Y.; Howard, C.J., The microwave spectrum of HO2 near 65 GHz, J. Chem. Phys., 1975, 63, 10, 4212, https://doi.org/10.1063/1.431191 . [all data]

Beers and Howard, 1976
Beers, Y.; Howard, C.J., The spectrum of DO2 near 60 GHz and the structure of the hydroperoxyl radical, J. Chem. Phys., 1976, 64, 4, 1541, https://doi.org/10.1063/1.432375 . [all data]

Saito, 1977
Saito, S., Microwave spectrum of the HO2 radical, J. Mol. Spectrosc., 1977, 65, 2, 229, https://doi.org/10.1016/0022-2852(77)90190-4 . [all data]

Tuckett, Freedman, et al., 1979, 2
Tuckett, R.P.; Freedman, P.A.; Jones, W.J., The near infra-red emission band of DO, Mol. Phys., 1979, 37, 2, 403, https://doi.org/10.1080/00268977900100341 . [all data]

McKellar, 1979
McKellar, A.R.W., Laser magnetic resonance spectroscopy of the ν2 fundamental band of DO2 at 9.8 μm, J. Chem. Phys., 1979, 71, 1, 81, https://doi.org/10.1063/1.438060 . [all data]

Barnes, Brown, et al., 1980
Barnes, C.E.; Brown, J.M.; Radford, H.E., The EPR and LMR spectra of the DO2 radical: Determination of ground-state parameters, J. Mol. Spectrosc., 1980, 84, 1, 179, https://doi.org/10.1016/0022-2852(80)90252-0 . [all data]

Charo and De Lucia, 1982
Charo, A.; De Lucia, F.C., The millimeter and submillimeter spectrum of HO2: The effects of unpaired electronic spin in a light asymmetric rotor, J. Mol. Spectrosc., 1982, 94, 2, 426, https://doi.org/10.1016/0022-2852(82)90018-2 . [all data]

Saito, Endo, et al., 1983
Saito, S.; Endo, Y.; Hirota, E., The microwave spectrum of the DO2 radical, J. Mol. Spectrosc., 1983, 98, 1, 183, https://doi.org/10.1016/0022-2852(83)90208-4 . [all data]

Lubic, Amano, et al., 1984
Lubic, K.G.; Amano, T.; Uehara, H.; Kawaguchi, K.; Hirota, E., The ν1 band of the DO2 radical by difference frequency laser and diode laser spectroscopy: The equilibrium structure of the hydroperoxyl radical, J. Chem. Phys., 1984, 81, 11, 4826, https://doi.org/10.1063/1.447508 . [all data]

Uehara, Kawaguchi, et al., 1985
Uehara, H.; Kawaguchi, K.; Hirota, E., Diode laser spectroscopy of the ν3 and ν2 fundamental bands of DO2, J. Chem. Phys., 1985, 83, 11, 5479, https://doi.org/10.1063/1.449668 . [all data]

Sears, Takacs, et al., 1986
Sears, T.J.; Takacs, G.A.; Howard, C.J.; Crownover, R.L.; Helminger, P.; De Lucia, F.C., Rotational spectroscopy of DO2 by FIR LMR and millimeter-wave absorption, J. Mol. Spectrosc., 1986, 118, 1, 103, https://doi.org/10.1016/0022-2852(86)90228-6 . [all data]

Chance, Park, et al., 1995
Chance, K.V.; Park, K.; Evenson, K.M.; Zink, L.R.; Stroh, F., Far-Infrared Spectrum of HO2, J. Mol. Spectrosc., 1995, 172, 2, 407, https://doi.org/10.1006/jmsp.1995.1188 . [all data]

Chance, Ramsay, et al., 2001
Chance, K.V.; Ramsay, D.A.; Fink, E.H., Improved Molecular Constants for the Ground State of DO2, J. Mol. Spectrosc., 2001, 207, 1, 123, https://doi.org/10.1006/jmsp.2001.8310 . [all data]

Fink and Ramsay, 2002
Fink, E.H.; Ramsay, D.A., High-Resolution Study of the Atilde;2A´→X2A´´ Transition of DO2: Analysis of the 000--000 Band, J. Mol. Spectrosc., 2002, 216, 2, 322, https://doi.org/10.1006/jmsp.2002.8621 . [all data]

DeSain, Ho, et al., 2003
DeSain, J.D.; Ho, A.D.; Taatjes, C.A., High-resolution diode laser absorption spectroscopy of the O--H stretch overtone band (2,0,0)←(0,0,0) of the HO2 radical, J. Mol. Spectrosc., 2003, 219, 1, 163, https://doi.org/10.1016/S0022-2852(03)00022-5 . [all data]

Wang and Andrews, 2005
Wang, X.; Andrews, L., Infrared Spectrum of Hg(OH), Inorg. Chem., 2005, 44, 1, 108, https://doi.org/10.1021/ic048673w . [all data]

Fink and Ramsay, 2006
Fink, E.H.; Ramsay, D.A., Analysis of perturbations in the state of HO2, J. Mol. Struct., 2006, 795, 1-3, 155, https://doi.org/10.1016/j.molstruc.2005.11.045 . [all data]


Notes

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References