Hypochlorous acid

• Formula: ClHO
• Molecular weight: 52.460
• IUPAC Standard InChI: InChI=1S/ClHO/c1-2/h2H Copy

  
• IUPAC Standard InChIKey: QWPPOHNGKGFGJK-UHFFFAOYSA-N Copy
• CAS Registry Number: 7790-92-3
• 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.
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Henry's Law data
• 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

Go To: Top, Gas phase ion energetics 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.

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 (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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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 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

Ionization energy determinations

De-protonation reactions

ClO^- +  =

By formula: ClO^- + H⁺ = HClO

Vibrational and/or electronic energy levels

Go To: Top, Gas phase 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 as indicated in comments:
J - Marilyn E. Jacox
Shim - Takehiko Shimanouchi

State:   X

Additional references: Jacox, 1994, page 52; Jacox, 1998, page 155; Jacox, 2003, page 45; Mirri, Scappini, et al., 1971; Gillis Singbeil, Anderson, et al., 1984; Anderson, Gerry, et al., 1986; Deeley, 1987; Bellini, De Natale, et al., 1995; Vander Auwera, Kleffmann, et al., 2000; Zheng, Ulenikov, et al., 2001

References

Go To: Top, Gas phase 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.

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

Colbourne, Frost, et al., 1978
Colbourne, D.; Frost, D.C.; McDowell, C.A.; Westwood, N.P.C., The photoelectron spectra of the isoelectronic molecules hypochlorous acid HOCl chloramine NH₂Cl, J. Chem. Phys., 1978, 68, 3574. [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]

Distelrath and Boesl, 2000
Distelrath, V.; Boesl, U., Mass selective gas phase study of ClO, OClO, ClOO and ClAr by anion-ZEKE-photoelectron spectroscopy, Faraday Disc. Chem. Soc., 2000, 115, 161-174, https://doi.org/10.1039/a909618c . [all data]

Ashby, 1967
Ashby, R.A., The infrared spectrum of HOCl, J. Mol. Spectrosc., 1967, 23, 4, 439, https://doi.org/10.1016/0022-2852(67)90122-1 . [all data]

Su, Calvert, et al., 1979
Su, F.; Calvert, J.G.; Lindley, C.R.; Uselman, W.M.; Shaw, J.H., Fourier transform infrared kinetic study of hypochlorous acid and its absolute integrated infrared band intensities, J. Phys. Chem., 1979, 83, 8, 912, https://doi.org/10.1021/j100471a006 . [all data]

Wells, Sams, et al., 1979
Wells, J.S.; Sams, R.L.; Lafferty, W.J., The high resolution infrared spectrum of the ν1 band of HOCl, J. Mol. Spectrosc., 1979, 77, 3, 349, https://doi.org/10.1016/0022-2852(79)90177-2 . [all data]

Deeley and Mills, 1985
Deeley, C.M.; Mills, I.M., Vibration-rotation spectra and the harmonic force field of HOCl, J. Mol. Spectrosc., 1985, 114, 2, 368, https://doi.org/10.1016/0022-2852(85)90232-2 . [all data]

Junttila, Lafferty, et al., 1994
Junttila, M.-L.; Lafferty, W.J.; Burkholder, J.B., The High-Resolution Spectrum of the ν1 Band and Ground State Rotational Constants of HOCl, J. Mol. Spectrosc., 1994, 164, 2, 583, https://doi.org/10.1006/jmsp.1994.1102 . [all data]

Raston, Kelloway, et al., 2012
Raston, P.L.; Kelloway, D.D.; Jager, W., Infrared spectroscopy of HOCl embedded in superfluid helium nanodroplets: Probing the dynamical response of the solvent, J. Chem. Phys., 2012, 137, 1, 014302, https://doi.org/10.1063/1.4731283 . [all data]

Yoshinobu, Akai, et al., 2009
Yoshinobu, T.; Akai, N.; Kawai, A.; Shibuya, K., Neon matrix-isolation infrared spectrum of HOOCl measured upon the VUV-light irradiation of an HCl/O2 mixture, Chem. Phys. Lett., 2009, 477, 1-3, 70, https://doi.org/10.1016/j.cplett.2009.06.064 . [all data]

Schwager and Arkell, 1967
Schwager, I.; Arkell, A., None, J. Am. Chem. Soc., 1967, 89, 24, 6006, https://doi.org/10.1021/ja01000a002 . [all data]

Hedberg and Badger, 1951
Hedberg, K.; Badger, R.M., The Infrared Spectra of HOCl and DOCl, J. Chem. Phys., 1951, 19, 4, 508, https://doi.org/10.1063/1.1748265 . [all data]

Ashby, 1971
Ashby, R.A., On the infrared spectrum of HOCl, J. Mol. Spectrosc., 1971, 40, 3, 639, https://doi.org/10.1016/0022-2852(71)90264-5 . [all data]

Niki, Maker, et al., 1979
Niki, H.; Maker, P.D.; Savage, C.M.; Breitenbach, L.P., Fourier transform IR spectroscopic determination of the equilibrium constant for H2O + Cl2O = 2HOCl, Chem. Phys. lett., 1979, 66, 2, 325, https://doi.org/10.1016/0009-2614(79)85027-7 . [all data]

Sams and Olson, 1980
Sams, R.L.; Olson, W.B., Analysis of the high-resolution infrared spectrum of the ν2 bending mode of HOCl at 1238 cm-1, J. Mol. Spectrosc., 1980, 84, 1, 113, https://doi.org/10.1016/0022-2852(80)90244-1 . [all data]

Lafferty and Olson, 1986
Lafferty, W.J.; Olson, W.B., The high-resolution infrared spectra of the ν2 and ν3 bands of HOCl, J. Mol. Spectrosc., 1986, 120, 2, 359, https://doi.org/10.1016/0022-2852(86)90010-X . [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]

Mirri, Scappini, et al., 1971
Mirri, A.M.; Scappini, F.; Cazzoli, G., Microwave spectrum, structure and electric quadrupole coupling constants of HOCl, J. Mol. Spectrosc., 1971, 38, 2, 218, https://doi.org/10.1016/0022-2852(71)90107-X . [all data]

Gillis Singbeil, Anderson, et al., 1984
Gillis Singbeil, H.E.; Anderson, W.D.; Davis, R.W.; Gerry, M.C.L.; Cohen, E.A.; Pickett, H.M.; Lovas, F.J.; Suenram, R.D., The microwave and millimeter-wave spectra of hypochlorous acid, J. Mol. Spectrosc., 1984, 103, 2, 466, https://doi.org/10.1016/0022-2852(84)90069-9 . [all data]

Anderson, Gerry, et al., 1986
Anderson, W.D.; Gerry, M.C.L.; Davis, R.W., The microwave spectrum of isotopically substituted hypochlorous acid: Determination of the molecular structure, J. Mol. Spectrosc., 1986, 115, 1, 117, https://doi.org/10.1016/0022-2852(86)90280-8 . [all data]

Deeley, 1987
Deeley, C.M., Vibration-rotation spectra of deuterated hypochlorous acid and the determination of the equilibrium structure, J. Mol. Spectrosc., 1987, 122, 2, 481, https://doi.org/10.1016/0022-2852(87)90022-1 . [all data]

Bellini, De Natale, et al., 1995
Bellini, M.; De Natale, P.; Fusina, L.; Modugno, G., The Pure Rotation Spectrum of HOCl in the Submillimeter-Wave Region, J. Mol. Spectrosc., 1995, 172, 2, 559, https://doi.org/10.1006/jmsp.1995.1202 . [all data]

Vander Auwera, Kleffmann, et al., 2000
Vander Auwera, J.; Kleffmann, J.; Flaud, J.-M.; Pawelke, G.; Burger, H.; Hurtmans, D.; Petrisse, R., Absolute ν2 Line Intensities of HOCl by Simultaneous Measurements in the Infrared with a Tunable Diode Laser and Far-Infrared Region Using a Fourier Transform Spectrometer, J. Mol. Spectrosc., 2000, 204, 1, 36, https://doi.org/10.1006/jmsp.2000.8197 . [all data]

Zheng, Ulenikov, et al., 2001
Zheng, J.-J.; Ulenikov, O.N.; Bekhtereva, E.S.; Ding, Y.; He, S.-G.; Hu, S.-M.; Wang, X.-H.; Zhu, Q.-S., High-Resolution Rotational Analysis of Deuterated Hypochlorous Acid: Ground State, (100), and (020) Vibrational States, J. Mol. Spectrosc., 2001, 209, 1, 105, https://doi.org/10.1006/jmsp.2001.8412 . [all data]

Notes

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

• Symbols used in this document:
  

  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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