Monochlorine monoxide
- Formula: ClO
- Molecular weight: 51.452
- IUPAC Standard InChIKey: NHYCGSASNAIGLD-UHFFFAOYSA-N
- 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
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Gas phase thermochemistry data
Go To: Top, Reaction thermochemistry data, 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.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 24.192 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1992 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 54.171 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in December, 1992 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = 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
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 600. | 600. to 6000. |
---|---|---|
A | 4.473631 | 8.842371 |
B | 14.12040 | 0.178913 |
C | -17.64410 | -0.016138 |
D | 8.260569 | 0.001251 |
E | 0.018271 | -0.188245 |
F | 22.43140 | 20.97330 |
G | 56.18800 | 63.91850 |
H | 24.19190 | 24.19190 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in December, 1992 | Data last reviewed in December, 1992 |
Reaction thermochemistry data
Go To: Top, Gas phase thermochemistry data, 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.
Data compiled by: John E. Bartmess
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
(CAS Reg. No. 80424-04-0 • 4294967295) + = CAS Reg. No. 80424-04-0
By formula: (CAS Reg. No. 80424-04-0 • 4294967295ClO) + ClO = CAS Reg. No. 80424-04-0
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 74.5 ± 1.4 | kcal/mol | N/A | Distelrath and Boesl, 2000 | gas phase; Reassignment of bands from Gilles, Polak, et al., 1992 |
ΔrH° | 79.9 ± 1.4 | kcal/mol | Ther | Gilles, Polak, et al., 1992 | gas phase |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Reaction 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 10.89 ± 0.02 | eV | N/A | N/A | L |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
2.2775 ± 0.0013 | ZEKE | Distelrath and Boesl, 2000 | B |
2.2760 ± 0.0060 | LPES | Gilles, Polak, et al., 1992 | B |
2.35 ± 0.15 | EIAE | Baluev, Nikitin, et al., 1980 | From Cl2O; B |
2.17 ± 0.23 | LPD | Lee, Smith, et al., 1979 | B |
1.95 ± 0.25 | IMRB | Dotan, Albritton, et al., 1978 | B |
>1.62 ± 0.22 | R-A | Vogt, Dreves, et al., 1977 | Cl- + O2 ->.; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.885 ± 0.016 | PI | Thorn, Stief, et al., 1996 | LL |
11.08 ± 0.05 | EI | Alekseev, Zyubina, et al., 1989 | LL |
11.0 | EVAL | Huber and Herzberg, 1979 | LLK |
10.95 | PE | Bulgin, Dyke, et al., 1979 | LLK |
11.1 ± 0.1 | EI | Fisher, 1967 | RDSH |
11.01 ± 0.01 | PE | Bulgin, Dyke, et al., 1979 | Vertical value; LLK |
Constants of diatomic molecules
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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: Klaus P. Huber and Gerhard H. Herzberg
Data collected through September, 1976
Symbol | Meaning |
---|---|
State | electronic state and / or symmetry symbol |
Te | minimum electronic energy (cm-1) |
ωe | vibrational constant – first term (cm-1) |
ωexe | vibrational constant – second term (cm-1) |
ωeye | vibrational constant – third term (cm-1) |
Be | rotational constant in equilibrium position (cm-1) |
αe | rotational constant – first term (cm-1) |
γe | rotation-vibration interaction constant (cm-1) |
De | centrifugal distortion constant (cm-1) |
βe | rotational constant – first term, centrifugal force (cm-1) |
re | internuclear distance (Å) |
Trans. | observed transition(s) corresponding to electronic state |
ν00 | position of 0-0 band (units noted in table) |
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
---|---|---|---|---|---|---|---|---|---|---|---|---|
Several unclassified absorption bands in the region 67000 - 79000 cm-1. | ||||||||||||
↳Basco and Morse, 1973 | ||||||||||||
H | (74125) | (1025) H | H ← X V | 74212 H | ||||||||
↳Basco and Morse, 1973 | ||||||||||||
G (2Π) | 73913 | 1075 H | 10 | G ← X V | 73705 H | |||||||
↳missing citation | ||||||||||||
73878 | 1075 H | 10 | G ← X V | 73986 H | ||||||||
↳missing citation | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
F (2Σ) | 69109 | [1001] 1 H | F ← X V | 68869 H | ||||||||
↳missing citation | ||||||||||||
69109 | [1001] 1 H | F ← X V | 69181 H | |||||||||
↳missing citation | ||||||||||||
E (2Σ) | 67333 | 1070 H | 4 | E ← X V | 67120 H | |||||||
↳missing citation | ||||||||||||
67333 | 1070 H | 4 | E ← X V | 67445 H | ||||||||
↳missing citation | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
D (2Σ) | 64486 | 1050 H | 2 | D ← X V | 64269 H | |||||||
↳missing citation | ||||||||||||
64486 | 1050 H | 2 | D ← X V | 64582 H | ||||||||
↳missing citation | ||||||||||||
C (2Σ) | 58448 | 1062 H | 3 | C ← X V | 58234 H | |||||||
↳missing citation | ||||||||||||
58448 | 1062 H | 3 | C ← X V | 58554 H | ||||||||
↳missing citation | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
A 2Πi | 32169 | 519.5 Z | 7.2 2 | -0.11 | 0.4450 3 | 0.006 | 0.000024 | [1.31E-6] | 1.858 | A ↔ X R | 31682.9 4 Z | |
↳Pannetier and Gaydon, 1948; Porter, 1950; missing citation; missing citation; missing citation; missing citation | ||||||||||||
31650 | 519.5 Z | 7.2 2 | -0.11 | 0.4450 3 | 0.006 | 0.000024 | [1.31E-6] | 1.858 | A ↔ X R | 31482.3 4 Z | ||
↳Pannetier and Gaydon, 1948; Porter, 1950; missing citation; missing citation; missing citation; missing citation | ||||||||||||
X 2Πi | 318 5 | 853.8 6 Z | 5.5 | -0.02 | 0.623448 7 | 0.0058 | 0.000016 | [1.33E-6] | 1.56963 8 | |||
↳Andrews and Raymond, 1971; Chi and Andrews, 1973 | ||||||||||||
0 | 853.8 6 Z | 5.5 | -0.02 | 0.623448 7 | 0.0058 | 0.000016 | [1.33E-6] | 1.56963 9 | ||||
↳Amano, Hirota, et al., 1968; Amano, Saito, et al., 1969 | ||||||||||||
EPR sp. 10 | ||||||||||||
↳Carrington, Dyer, et al., 1967; Carrington, Levy, et al., 1967; Uehara and Morino, 1970; Uehara, Tanimoto, et al., 1971 |
Notes
1 | ΔG(3/2) = 950, ΔG(5/2) = 980. |
2 | see 3 |
3 | In absorption observed to v'=25 of 2Π3/2 [Bv, Dv values in Coxon and Ramsay, 1976, Coxon, Jones, et al., 1976] close to the dissociation limit at 38052 cm-1 above X 2Π3/2(v=0). The constants are for levels with v≤9. All absorption and emission bands are diffuse on account of predissociation. Linewidths in different bands vary from 0.3 to 3.1 cm-1 and are >5 cm-1 in v'=6 Coxon and Ramsay, 1976. |
4 | Note that there have been several changes of vibrational numbering [see, e.g., Briggs, 1972]; here we have used that of Coxon and Ramsay, 1976 and Coxon, Jones, et al., 1976. |
5 | From the VUV absorption spectrum Basco and Morse, 1973; confirmed by EPR spectrum Carrington, Dyer, et al., 1967, Uehara, Tanimoto, et al., 1971. |
6 | missing note |
7 | From combined microwave and ultraviolet data; the microwave values of Amano, Saito, et al., 1969 are B0(2Π3/2) = 0.6l9773 and B0(2Π1/2) = 0.621231. Λ-type doubling in the 2Π1/2 component, Δvfe = +0.02249(J+1/2). |
8 | Matrix IR and Raman sp. |
9 | Microwave sp. 10 |
10 | Dipole moment from Stark effect of microwave spectrum μel(v=0) = 1.239 D Amano, Saito, et al., 1969, from Stark effect of EPR spectrum 1.18D Carrington, Levy, et al., 1967. eqQ and other hyperfine structure constants in Amano, Saito, et al., 1969, Uehara, Tanimoto, et al., 1971 |
11 | From the convergence limit of the A ← X, 2Π3/2 ← 2Π3/2 subbands Coxon and Ramsay, 1976 assuming dissociation into 2P3/2 + 1D |
12 | Mass-spectrometric studies and theoretical calculations; see O'Hare and Wahl, 1971. |
13 | The effective we values for 2Π1/2 and 2Π3/2 are 853.0 and 854.9 cm-1, respectively Coxon, Jones, et al., 1976. |
14 | Indirectly from thermochemical data and mass-spectrometric studies; also theoretical calculations; see O'Hare and Wahl, 1971. |
References
Go To: Top, Gas phase thermochemistry data, Reaction 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 (2Π3/2) 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 A2Πi-X2Πi 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 A2Πi-X2Πi 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, Reaction 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 ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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