Monochlorine monoxide

• Formula: ClO
• Molecular weight: 51.452
• IUPAC Standard InChI: InChI=1S/ClO/c1-2 Copy

  
• IUPAC Standard InChIKey: NHYCGSASNAIGLD-UHFFFAOYSA-N Copy
• CAS Registry Number: 14989-30-1
• 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.
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • Constants of diatomic molecules
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, Constants of diatomic molecules, 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.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Constants of diatomic molecules, 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:
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 ClO⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Constants of diatomic molecules

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 by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through September, 1976

Notes

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, 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]

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]

Gilles, Polak, et al., 1992
Gilles, M.K.; Polak, M.L.; Lineberger, W.C., Photoelectron Spectroscopy of the Halogen Oxide Anions FO-, ClO-, BrO-, IO-, OClO-, and OIO-, J. Chem. Phys., 1992, 96, 11, 8012, https://doi.org/10.1063/1.462352 . [all data]

Baluev, Nikitin, et al., 1980
Baluev, A.V.; Nikitin, I.M.; Fedorova, L.I.; Rossolovskii, V.Ya., Mass Spectrometric Study of Chlorine Pentafluoride Ionization by Electron Impact, Izv. Akad. Nauk SSR Ser. Khim. 487, 1980. [all data]

Lee, Smith, et al., 1979
Lee, L.C.; Smith, G.P.; Moseley, J.T.; Cosby, P.C.; Guest, J.A., Photodissociation and photodetachment of Cl₂-, ClO-, Cl₃-, and BrCl₂-, J. Chem. Phys., 1979, 70, 3237. [all data]

Dotan, Albritton, et al., 1978
Dotan, I.; Albritton, D.L.; Fehsenfeld, F.C.; Streit, G.E.; Ferguson, E.E., Rate constants for the reactions of O^-, O₂^-, NO₂^-, CO₃^-, and CO₄^- with HCl and ClO- with NO, NO₂, SO₂, and CO₂ at 300K, J. Chem. Phys., 1978, 68, 5414. [all data]

Vogt, Dreves, et al., 1977
Vogt, D.; Dreves, W.; Mischke, J., Energy dependence of differential cross sections in endoergic ion-molecule collision processes of negative ions, Int. J. Mass Spectrom. Ion Phys., 1977, 24, 285. [all data]

Thorn, Stief, et al., 1996
Thorn, R.P., Jr.; Stief, L.J.; Kuo, S.-C.; Klemm, R.B., Ionization energy of Cl₂O and ClO, appearance energy of ClO⁺(Cl₂O), and heat of formation of Cl₂O, J. Phys. Chem., 1996, 100, 14178. [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]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Bulgin, Dyke, et al., 1979
Bulgin, D.K.; Dyke, J.M.; Jonathan, N.; Morris, A., Vacuum ultraviolet photoelectron spectroscopy of transient species, J. Chem. Soc. Faraday Trans. 2, 1979, 75, 456. [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]

Basco and Morse, 1973
Basco, N.; Morse, R.D., The vacuum ultraviolet absorption spectrum of ClO, J. Mol. Spectrosc., 1973, 45, 35. [all data]

Pannetier and Gaydon, 1948
Pannetier, G.; Gaydon, A.G., Band spectrum of ClO in flames, Nature (London), 1948, 161, 242. [all data]

Porter, 1950
Porter, G., The absorption spectroscopy of substances of short life, Discuss. Faraday Soc., 1950, 9, 60, https://doi.org/10.1039/df9500900060 . [all data]

Andrews and Raymond, 1971
Andrews, L.; Raymond, J.I., Argon matrix infrared spectrum of the ClO radical, J. Chem. Phys., 1971, 55, 3087. [all data]

Chi and Andrews, 1973
Chi, F.K.; Andrews, L., Argon matrix Raman spectra of dichlorine monoxide and its photolysis products monochlorine monoxide and chlorine-monochlorine monoxide. Infrared matrix spectra of monochlorine monoxide and dimeric monochlorine monoxide, J. Phys. Chem., 1973, 77, 26, 3062, https://doi.org/10.1021/j100644a007 . [all data]

Amano, Hirota, et al., 1968
Amano, T.; Hirota, E.; Morino, Y., Microwave spectrum of the ClO radical, J. Mol. Spectrosc., 1968, 27, 257. [all data]

Amano, Saito, et al., 1969
Amano, T.; Saito, S.; Hirota, E.; Morino, Y., Microwave spectrum of the ClO radical, J. Mol. Spectrosc., 1969, 30, 275. [all data]

Carrington, Dyer, et al., 1967
Carrington, A.; Dyer, P.N.; Levy, D.H., Gas-phase electron resonance spectrum of ClO, J. Chem. Phys., 1967, 47, 1756. [all data]

Carrington, Levy, et al., 1967
Carrington, A.; Levy, D.H.; Miller, T.A., Stark effect in gas-phase electron resonance. The dipole moments of ClO, BrO, SH, and ¹ΔSO, J. Chem. Phys., 1967, 47, 3801. [all data]

Uehara and Morino, 1970
Uehara, H.; Morino, Y., Gas-phase EPR spectra of rotationally excited states of SH and ClO free radicals, J. Mol. Spectrosc., 1970, 36, 158. [all data]

Uehara, Tanimoto, et al., 1971
Uehara, H.; Tanimoto, M.; Morino, Y., Hyperfine interactions in the gas-phase E.P.R. spectra of ³⁵ClO (²Π_3/2) in the J=5/2 and J=3/2 levels, Mol. Phys., 1971, 22, 799. [all data]

Coxon and Ramsay, 1976
Coxon, J.A.; Ramsay, D.A., The A²Π_i-X²Π_i band system of ClO: reinvestigation of the absorption spectrum, Can. J. Phys., 1976, 54, 1034. [all data]

Coxon, Jones, et al., 1976
Coxon, J.A.; Jones, W.E.; Skolnik, E.G., Rotational analysis of emission bands of the A²Π_i-X²Π_i system of ³⁵ClO, Can. J. Phys., 1976, 54, 1043. [all data]

Briggs, 1972
Briggs, A.G., Vibrational reassignments in the A²Π-X²Π system of ClO, Nature (London), 1972, 239, 13. [all data]

O'Hare and Wahl, 1971
O'Hare, P.A.G.; Wahl, A.C., Dissociation energy, ionization potential, electron affinity, dipole and quadrupole moments of chlorine monoxide (ClO,²Π) from ab initio molecular orbital calculations, J. Chem. Phys., 1971, 54, 3770. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References

• Symbols used in this document:
  

  EA	Electron affinity
  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

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.