Chlorine dioxide

• Formula: ClO₂
• Molecular weight: 67.452
• IUPAC Standard InChI: InChI=1S/ClO2/c2-1-3 Copy

  
• IUPAC Standard InChIKey: OSVXSBDYLRYLIG-UHFFFAOYSA-N Copy
• CAS Registry Number: 10049-04-4
• 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.
• Other names: Chlorine oxide (ClO2); Chlorine(IV) oxide; Chloryl radical; Doxcide 50; Chlorine oxide; ClO2; Alcide; Anthium dioxcide; Chlorine peroxide; Chloroperoxyl
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Henry's Law data
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • 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.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Phase change 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.

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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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:
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

View reactions leading to ClO₂⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

Vibrational and/or electronic energy levels

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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: Marilyn E. Jacox

State:   E

State:   D

State:   C

State:   A

State:   A'

State:   X

Additional references: Jacox, 1994, page 113; Jacox, 1998, page 205; Jacox, 2003, page 149; Curl, Kinsey, et al., 1961; Curl, Heidelberg, et al., 1962; Curl, 1962; Tolles, Kinsey, et al., 1962; Pillai and Curl, 1962; Coon, Cesani, et al., 1963; McDonald and Innes, 1978; Michielsen, Merer, et al., 1981; Tanoura, Chiba, et al., 1982; Brockmann and Haaks, 1986; Miyazaki, Tanoura, et al., 1986; Peterson and Werner, 1992

Notes

References

Go To: Top, Gas phase thermochemistry data, Phase change 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.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Flesch, Ruhl, et al., 1993
Flesch, R.; Ruhl, E.; Hottmann, K.; Baumgartel, H., Photoabsorption and photoionization of chlorine dioxide, J. Phys. Chem., 1993, 97, 837. [all data]

Alekseev, Zyubina, et al., 1989
Alekseev, V.I.; Zyubina, T.S.; Zyubin, A.S.; Baluev, A.V., Mass-spectrometric and quantum-chemical investigation of thermochemical characteristics of chlorine oxides, J. Am. Chem. Soc., 1989, 2092. [all data]

Baluev, Nikitina, et al., 1980
Baluev, A.V.; Nikitina, Z.K.; Fedorova, L.I.; Rosolovskii, V.Ya., Mass spectrometric investigation of electron-impact induced ionization of chlorine dioxide and chloryl fluoride molecules, Izv. Akad. Nauk SSSR, Ser. Khim., 1980, 1963. [all data]

Cornford, Frost, et al., 1971
Cornford, A.B.; Frost, D.C.; Herring, F.G.; McDowell, C.A., The photoelectron spectrum of the free radical chlorine dioxide, Chem. Phys. Lett., 1971, 10, 345. [all data]

Fisher, 1967
Fisher, I.P., Mass spectrometry study of intermediates in thermal decomposition of perchloric acid and chlorine dioxide, J. Chem. Soc. Faraday Trans., 1967, 63, 684. [all data]

Cornford, Frost, et al., 1972
Cornford, A.B.; Frost, D.C.; Herring, F.G.; McDowell, C.A., Photoelectron spectra of some free radicals, Faraday Discuss. Chem. Soc., 1972, 54, 56. [all data]

Humphries, Walsh, et al., 1963
Humphries, C.M.; Walsh, A.D.; Warsop, P.A., Absorption spectrum of chlorine dioxide in the vacuum ultra-violet, Discuss. Faraday Soc., 1963, 35, 137, https://doi.org/10.1039/df9633500137 . [all data]

Basco and Morse, 1974
Basco, N.; Morse, R.D., Reactions of Halogen Oxides Studied by Flash Photolysis. IV. Vacuum Ultraviolet Kinetic Spectroscopy Studies on Chlorine Dioxide, Proc. Roy. Soc. (London) A336, 1974, 336, 1607, 495, https://doi.org/10.1098/rspa.1974.0032 . [all data]

Hubinger and Nee, 1994
Hubinger, S.; Nee, J.B., Photoabsorpton spectrum for OClO between 125 and 470 nm, Chem. Phys., 1994, 181, 1-2, 247, https://doi.org/10.1016/0301-0104(94)85027-5 . [all data]

Urey and Johnston, 1931
Urey, H.C.; Johnston, H., The Absorption Spectrum of Chlorine Dioxide, Phys. Rev., 1931, 38, 12, 2131, https://doi.org/10.1103/PhysRev.38.2131 . [all data]

Coon, 1946
Coon, J.B., Rotational Structure of Some Electronic Bands of Chlorine Dioxide, J. Chem. Phys., 1946, 14, 11, 665, https://doi.org/10.1063/1.1724083 . [all data]

Coon and Ortiz, 1957
Coon, J.B.; Ortiz, E., The vibrational analysis of the 2700--4800 A absorption system of ClO2 and the vibrational constants of the associated electronic states, J. Mol. Spectrosc., 1957, 1, 1-4, 81, https://doi.org/10.1016/0022-2852(57)90012-7 . [all data]

Richardson, Redding, et al., 1969
Richardson, A.W.; Redding, R.W.; Brand, J.C.D., The 4750 Å band system of chlorine dioxide, J. Mol. Spectrosc., 1969, 29, 1-3, 93, https://doi.org/10.1016/0022-2852(69)90086-1 . [all data]

Sakurai, Clark, et al., 1971
Sakurai, K.; Clark, J.; Broida, H.P., Laser Induced Fluorescence of ClO2, J. Chem. Phys., 1971, 54, 3, 1217, https://doi.org/10.1063/1.1674957 . [all data]

Curl, Abe, et al., 1973
Curl, R.F.; Abe, K.; Bissinger, J.; Bennett, C.; Tittel, F.K., Fluorescence spectrum of chlorine dioxide induced by the 4765 Å argon-ion laser line, J. Mol. Spectrosc., 1973, 48, 1, 72, https://doi.org/10.1016/0022-2852(73)90136-7 . [all data]

Hamada, Merer, et al., 1981
Hamada, Y.; Merer, A.J.; Michielsen, S.; Rice, S.A., Rotational analysis of bands at the long-wavelength end of the electronic transition of ClO2, J. Mol. Spectrosc., 1981, 86, 2, 499, https://doi.org/10.1016/0022-2852(81)90297-6 . [all data]

Wahner, Tyndall, et al., 1987
Wahner, A.; Tyndall, G.S.; Ravishankara, A.R., Absorption cross sections for symmetric chlorine dioxide as a function of temperature in the wavelength range 240-480nm, J. Phys. Chem., 1987, 91, 11, 2734, https://doi.org/10.1021/j100295a018 . [all data]

Richard, Wickham-Jones, et al., 1989
Richard, E.C.; Wickham-Jones, C.T.; Vaida, V., Fourier transform ultraviolet absorption spectroscopy of jet-cooled chlorine dioxide, J. Phys. Chem., 1989, 93, 17, 6346, https://doi.org/10.1021/j100354a016 . [all data]

Ruhl, Jefferson, et al., 1990
Ruhl, E.; Jefferson, A.; Vaida, V., Photodissociation of chlorine oxide (OClO): REMPI study of primary photofragments, J. Phys. Chem., 1990, 94, 7, 2990, https://doi.org/10.1021/j100370a047 . [all data]

Richard and Vaida, 1991
Richard, E.C.; Vaida, V., The direct near ultraviolet absorption spectrum of the A 2A2←X 2B1 transition of jet-cooled chlorine dioxide, J. Chem. Phys., 1991, 94, 1, 153, https://doi.org/10.1063/1.460389 . [all data]

Richard and Vaida, 1991, 2
Richard, E.C.; Vaida, V., The photochemical dynamics of the A 2A2 state of chlorine dioxide, J. Chem. Phys., 1991, 94, 1, 163, https://doi.org/10.1063/1.460390 . [all data]

Bishenden, Haddock, et al., 1991
Bishenden, E.; Haddock, J.; Donaldson, D.J., Resonance-enhanced multiphoton ionization (REMPI) measurement of atomic chlorine(2P3/2 and 2P1/2) produced in the photolysis of chlorine dioxide (OClO) from 355 to 370 nm, J. Phys. Chem., 1991, 95, 6, 2113, https://doi.org/10.1021/j100159a006 . [all data]

Davis and Lee, 1992
Davis, H.F.; Lee, Y.T., Dynamics and mode specificity in OClO photodissociation, J. Phys. Chem., 1992, 96, 14, 5681, https://doi.org/10.1021/j100193a005 . [all data]

Bishenden and Donaldson, 1993
Bishenden, E.; Donaldson, D.J., Mode-specific chemical branching ratios in the photodissociation of OClO, J. Chem. Phys., 1993, 99, 4, 3129, https://doi.org/10.1063/1.465167 . [all data]

Bishenden and Donaldson, 1994
Bishenden, E.; Donaldson, D.J., Two primary product channels in OClO photodissociation near 360 nm, J. Chem. Phys., 1994, 101, 11, 9565, https://doi.org/10.1063/1.468445 . [all data]

Davis and Lee, 1996
Davis, H.F.; Lee, Y.T., Photodissociation dynamics of OClO, J. Chem. Phys., 1996, 105, 18, 8142, https://doi.org/10.1063/1.472700 . [all data]

Lim, Kim, et al., 1999
Lim, S.-M.; Kim, T.-S.; -Il Lim, G.; Kim, D.K.; Choi, Y.S., Fluorescence Excitation Spectrum of OClO (Ã, J. Phys. Chem. A, 1999, 103, 13, 2097, https://doi.org/10.1021/jp9847888 . [all data]

Liu, Lai, et al., 1998
Liu, C.-P.; Lai, L.-H.; Lee, Y.-Y.; Hung, S.-C.; Lee, Y.-P., Absorption and fluorescence of OClO A [sup 2]A[sub 2]--X [sup 2]B[sub 1] in solid Ne, Ar, and Kr. I. Vibrationally unrelaxed A→X emission, J. Chem. Phys., 1998, 109, 3, 978, https://doi.org/10.1063/1.476668 . [all data]

Wang and Wang, 2000
Wang, W.-B.; Wang, L.-S., The electronic structure and electron affinities of higher chlorine oxide radicals ClO[sub x] (x=2--4) from photoelectron spectroscopy of ClO[sub x][sup -] anions, J. Chem. Phys., 2000, 113, 24, 10928, https://doi.org/10.1063/1.1326067 . [all data]

Hedberg, 1951
Hedberg, K., The Infrared Spectra of Cl2O and ClO2, J. Chem. Phys., 1951, 19, 4, 509, https://doi.org/10.1063/1.1748266 . [all data]

Nielsen and Woltz, 1952
Nielsen, A.H.; Woltz, P.J.H., The Infrared Spectrum of Chlorine Dioxide, J. Chem. Phys., 1952, 20, 12, 1878, https://doi.org/10.1063/1.1700331 . [all data]

Esposito, Stedl, et al., 1999
Esposito, A.P.; Stedl, T.; Jonsson, H.; Reid, P.J.; Peterson, K.A., Absorption and Resonance Raman Study of the, J. Phys. Chem. A, 1999, 103, 12, 1748, https://doi.org/10.1021/jp984368i . [all data]

Uehara and Hakuta, 1978
Uehara, H.; Hakuta, K., Laser magnetic resonance spectra of ClO2 tuned by the avoidance of zeeman level crossing, Chem. Phys. Lett., 1978, 58, 2, 287, https://doi.org/10.1016/0009-2614(78)80295-4 . [all data]

Hamada and Tsuboi, 1980
Hamada, Y.; Tsuboi, T., High-resolution infrared spectrum of chlorine dioxide: The ν1 fundamental band, J. Mol. Spectrosc., 1980, 83, 2, 373, https://doi.org/10.1016/0022-2852(80)90062-4 . [all data]

Jones and Brown, 1981
Jones, H.; Brown, J.M., Infrared-microwave double-resonance spectroscopy of the ClO2 radical: A textbook example, J. Mol. Spectrosc., 1981, 90, 1, 222, https://doi.org/10.1016/0022-2852(81)90343-X . [all data]

Tanaka and Tanaka, 1983
Tanaka, K.; Tanaka, T., CO2 and N2O laser Stark spectroscopy of the ν1 band of the ClO2 radical, J. Mol. Spectrosc., 1983, 98, 2, 425, https://doi.org/10.1016/0022-2852(83)90253-9 . [all data]

Ortigoso, Escribano, et al., 1991
Ortigoso, J.; Escribano, R.; Burkholder, J.B.; Howard, C.J.; Lafferty, W.J., High-resolution infrared spectrum of the ν1 band of OClO, J. Mol. Spectrosc., 1991, 148, 2, 346, https://doi.org/10.1016/0022-2852(91)90392-N . [all data]

Ortigoso, Escribano, et al., 1992
Ortigoso, J.; Escribano, R.; Burkholder, J.B.; Lafferty, W.J., Intensities and dipole moment derivatives of the fundamental bands of 35ClO2 and an intensity analysis of the ν1 band, J. Mol. Spectrosc., 1992, 156, 1, 89, https://doi.org/10.1016/0022-2852(92)90095-6 . [all data]

Muller and Willner, 1993
Muller, H.S.P.; Willner, H., Vibrational and electronic spectra of chlorine dioxide, OClO, and chlorine superoxide ClOO, isolated in cryogenic matrixes, J. Phys. Chem., 1993, 97, 41, 10589, https://doi.org/10.1021/j100143a013 . [all data]

Arkell and Schwager, 1967
Arkell, A.; Schwager, I., None, J. Am. Chem. Soc., 1967, 89, 24, 5999, https://doi.org/10.1021/ja01000a001 . [all data]

Tevault, Chi, et al., 1974
Tevault, D.E.; Chi, F.K.; Andrews, L., Infrared spectrum and vibrational potential function of the chlorite anion in the matrix-isolated M+ClO2- species, J. Mol. Spectrosc., 1974, 51, 3, 450, https://doi.org/10.1016/0022-2852(74)90200-8 . [all data]

Chi and Andrews, 1974
Chi, F.K.; Andrews, L., Resonance Raman and fluorescence spectra of chlorine dioxide in argon, krypton, xenon, and nitrogen matrices at 16 K, J. Mol. Spectrosc., 1974, 52, 1, 82, https://doi.org/10.1016/0022-2852(74)90007-1 . [all data]

Hamada and Tsuboi, 1979
Hamada, Y.; Tsuboi, M., High Resolution Infrared Spectrum of Chlorine Dioxide: The v2 Fundamental Band, Bull. Chem. Soc. Japan, 1979, 52, 2, 383, https://doi.org/10.1246/bcsj.52.383 . [all data]

Ortigoso, Escribano, et al., 1992, 2
Ortigoso, J.; Escribano, R.; Burkholder, J.B.; Lafferty, W.J., The ν2 and ν3 bands and ground state constants of OClO, J. Mol. Spectrosc., 1992, 155, 1, 25, https://doi.org/10.1016/0022-2852(92)90546-Z . [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]

Curl, Kinsey, et al., 1961
Curl, R.F., Jr.; Kinsey, J.L.; Baker, J.G.; Baird, J.C.; Bird, G.R.; Heidelberg, R.F.; Sugden, T.M.; Jenkins, D.R.; Kenney, C.N., Microwave Spectrum of Chlorine Dioxide. I. Rotational Assignment, Phys. Rev., 1961, 121, 4, 1119, https://doi.org/10.1103/PhysRev.121.1119 . [all data]

Curl, Heidelberg, et al., 1962
Curl, R.F.; Heidelberg, R.F.; Kinsey, J.L., Microwave Spectrum of Chlorine Dioxide. II. Analysis of Hyperfine Structure and the Spectrum of Cl35O16O18, Phys. Rev., 1962, 125, 6, 1993, https://doi.org/10.1103/PhysRev.125.1993 . [all data]

Curl, 1962
Curl, R.F., Jr., Microwave Spectrum of Chlorine Dioxide. III. Interpretation of the Hyperfine Coupling Constants Obtained in Terms of the Electronic Structure, J. Chem. Phys., 1962, 37, 4, 779, https://doi.org/10.1063/1.1733160 . [all data]

Tolles, Kinsey, et al., 1962
Tolles, W.M.; Kinsey, J.L.; Curl, R.F., Jr.; Heidelberg, R.F., Microwave Spectrum of Chlorine Dioxide. V. The Stark and Zeeman Effects, J. Chem. Phys., 1962, 37, 5, 927, https://doi.org/10.1063/1.1733247 . [all data]

Pillai and Curl, 1962
Pillai, M.G.K.; Curl, R.F., Microwave Spectrum of Chlorine Dioxide. IV. Determination of Centrifugal Distortion Effects and Potential Constants, J. Chem. Phys., 1962, 37, 12, 2921, https://doi.org/10.1063/1.1733118 . [all data]

Coon, Cesani, et al., 1963
Coon, J.B.; Cesani, F.A.; Loyd, C.M., Evidence for a double-minimum potential in an excited state of ClO2, Discuss. Faraday Soc., 1963, 35, 118, https://doi.org/10.1039/df9633500118 . [all data]

McDonald and Innes, 1978
McDonald, P.A.; Innes, K.K., Assignment of the mechanism of predissociation of the ClO2 molecule by analysis of single-rotational-level lifetimes, Chem. Phys. Lett., 1978, 59, 3, 562, https://doi.org/10.1016/0009-2614(78)85042-8 . [all data]

Michielsen, Merer, et al., 1981
Michielsen, S.; Merer, A.J.; Rice, S.A.; Novak, F.A.; Freed, K.A.; Hamada, Y.J., A study of the rotational state dependence of predissociation of a polyatomic molecule: The case of ClO2, J. Chem. Phys., 1981, 74, 6, 3089, https://doi.org/10.1063/1.441520 . [all data]

Tanoura, Chiba, et al., 1982
Tanoura, M.; Chiba, K.; Tanaka, K.; Tanaka, T., Microwave spectroscopy of chlorine dioxide, J. Mol. Spectrosc., 1982, 95, 1, 157, https://doi.org/10.1016/0022-2852(82)90245-4 . [all data]

Brockmann and Haaks, 1986
Brockmann, K.J.; Haaks, D., Methods of Laser Spectroscopy, Y. Prior, A. Ben-Reuven, and M. Rosenbluh, ed(s)., Plenum, NY, 1986, 411-415. [all data]

Miyazaki, Tanoura, et al., 1986
Miyazaki, K.; Tanoura, M.; Tanaka, K.; Tanaka, T., Microwave spectrum of chlorine dioxide in excited vibrational states, J. Mol. Spectrosc., 1986, 116, 2, 435, https://doi.org/10.1016/0022-2852(86)90138-4 . [all data]

Peterson and Werner, 1992
Peterson, K.A.; Werner, H., Multireference configuration interaction calculations of the low-lying electronic states of ClO2, J. Chem. Phys., 1992, 96, 12, 8948, https://doi.org/10.1063/1.462253 . [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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