Hydroxyl radical
- Formula: HO
- Molecular weight: 17.0073
- IUPAC Standard InChIKey: TUJKJAMUKRIRHC-UHFFFAOYSA-N
- CAS Registry Number: 3352-57-6
- Chemical structure:
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Reaction thermochemistry data
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: 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
O- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 382.600 ± 0.010 | kcal/mol | D-EA | Neumark, Lykke, et al., 1985 | gas phase; Given: 1.461122(3) eV; revised to 1.4611107(17) eV, 95BLO, based on missing term+86CODATA |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 376.73 ± 0.15 | kcal/mol | H-TS | Neumark, Lykke, et al., 1985 | gas phase; Given: 1.461122(3) eV; revised to 1.4611107(17) eV, 95BLO, based on missing term+86CODATA |
+ = HFO-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 32.4 ± 2.3 | kcal/mol | LPES | Deyerl and Continetti, 2005 | gas phase; affinity at 0 K |
By formula: H- + HO = (H- • HO)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 51.8 ± 4.1 | kcal/mol | Ther | de Koening and Nibbering, 1984 | gas phase |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, 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
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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 HO+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 13.017 ± 0.002 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 141.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 134.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
1.82767 | LPD | Smith, Kim, et al., 1997 | Given: 14741.02(3) cm-1. dHacid(0K) = 389.11±0.014; B |
1.827669 ± 0.000044 | LPD | Schulz, Mead, et al., 1982 | Given: 1.82767±0.00021 eV; B |
1.829 ± 0.010 | LPES | Celotta, Bennett, et al., 1974 | B |
1.8250 ± 0.0020 | LPD | Hotop, Patterson, et al., 1974 | B |
1.830 ± 0.040 | PD | Branscomb, 1966 | B |
1.80 ± 0.20 | EIAE | Tsuda and Hamill, 1964 | From MeOH,EtOH,nPrOH; B |
1.80321 | N/A | Check, Faust, et al., 2001 | MnBr3-; ; ΔS(EA)=1.7; B |
1.89 ± 0.12 | SI | Page and Goode, 1969 | The Magnetron method, lacking mass analysis, is not considered reliable.; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
13.0170 ± 0.0002 | TE | Wiedmann, Tonkyn, et al., 1992 | LL |
13.01 | PE | Van Lonkhuyzen and De Lange, 1984 | LBLHLM |
12.88 | DER | Berkowitz, Appelman, et al., 1973 | LLK |
13.5 ± 1.0 | EI | Uy, Srivastava, et al., 1971 | LLK |
12.94 | DER | Dibeler, Walker, et al., 1966 | RDSH |
13.2 ± 0.1 | EI | Foner and Hudson, 1956 | RDSH |
13.01 | PE | Katsumata and Lloyd, 1977 | Vertical value; LLK |
De-protonation reactions
O- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 382.600 ± 0.010 | kcal/mol | D-EA | Neumark, Lykke, et al., 1985 | gas phase; Given: 1.461122(3) eV; revised to 1.4611107(17) eV, 95BLO, based on missing term+86CODATA; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 376.73 ± 0.15 | kcal/mol | H-TS | Neumark, Lykke, et al., 1985 | gas phase; Given: 1.461122(3) eV; revised to 1.4611107(17) eV, 95BLO, based on missing term+86CODATA; B |
References
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Neumark, Lykke, et al., 1985
Neumark, D.M.; Lykke, K.R.; Andersen, T.; Lineberger, W.C.,
Laser photodetachment measurement of the electron affinity of atomic oxygen,
Phys. Rev. A:, 1985, 32, 1890. [all data]
Deyerl and Continetti, 2005
Deyerl, H.J.; Continetti, R.E.,
Photoelectron-photofragment coincidence study of OHF-: transition state dynamics of the reaction OH+F - O+HF,
Phys. Chem. Chem. Phys., 2005, 7, 5, 855-860, https://doi.org/10.1039/b414604b
. [all data]
de Koening and Nibbering, 1984
de Koening, L.J.; Nibbering, N.M.M.,
Formation of the Long-Lived H2O-. Ion in the Gas Phase,
J. Am. Chem. Soc., 1984, 106, 25, 7971, https://doi.org/10.1021/ja00337a054
. [all data]
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]
Smith, Kim, et al., 1997
Smith, J.R.; Kim, J.B.; Lineberger, W.C.,
High-resolution Threshold Photodetachment Spectroscopy of OH-,
Phys. Rev. A, 1997, 55, 3, 2036, https://doi.org/10.1103/PhysRevA.55.2036
. [all data]
Schulz, Mead, et al., 1982
Schulz, P.A.; Mead, R.D.; Jones, P.L.; Lineberger, W.C.,
OH- and OD- threshold photodetachment,
J. Chem. Phys., 1982, 77, 1153. [all data]
Celotta, Bennett, et al., 1974
Celotta, R.S.; Bennett, R.A.; Hall, J.L.,
Laser Photodetachment Determination of the Electron Affinities of OH, NH2, NH, SO2, and S2,
J. Chem. Phys., 1974, 60, 5, 1740, https://doi.org/10.1063/1.1681268
. [all data]
Hotop, Patterson, et al., 1974
Hotop, H.; Patterson, T.A.; Lineberger, W.C.,
High resolution photodetachment study of OH- and OD- in the threshold region 7000-6450 Å,
J. Chem. Phys., 1974, 60, 1806. [all data]
Branscomb, 1966
Branscomb, L.M.,
Photodetachment Cross Section, Electron Affinity, and Structure of the Negative Hydroxyl Ion,
Phys. Rev., 1966, 148, 1, 11, https://doi.org/10.1103/PhysRev.148.11
. [all data]
Tsuda and Hamill, 1964
Tsuda, S.; Hamill, W.H.,
Ionization Efficiency Measurements by the Retarding Potential Difference Method,
Adv. Mass Spectrom., 1964, 3, 249. [all data]
Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S.,
Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements,
J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l
. [all data]
Page and Goode, 1969
Page, F.M.; Goode, G.C.,
Negative Ions and the Magnetron., Wiley, NY, 1969. [all data]
Wiedmann, Tonkyn, et al., 1992
Wiedmann, R.T.; Tonkyn, R.G.; White, M.G.; Wang, K.; McKoy, V.,
Rotationally resolved threshold photoelectron spectra of OH and OD,
J. Chem. Phys., 1992, 97, 768. [all data]
Van Lonkhuyzen and De Lange, 1984
Van Lonkhuyzen, H.; De Lange, C.A.,
U. V. photoelectron spectroscopy of OH and OD radicals,
Mol. Phys., 1984, 51, 551. [all data]
Berkowitz, Appelman, et al., 1973
Berkowitz, J.; Appelman, E.H.; Chupka, W.A.,
Photoionization of HOF with mass analysis,
J. Chem. Phys., 1973, 58, 1950. [all data]
Uy, Srivastava, et al., 1971
Uy, O.M.; Srivastava, R.D.; Farber, M.,
Mass spectrometric determination of the heats of formation of gaseous BO2 BOF2,
High Temp. Sci., 1971, 3, 462. [all data]
Dibeler, Walker, et al., 1966
Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M.,
Mass spectrometric study of photoionization. V.Water and ammonia,
J.Res. NBS, 1966, 70A, 459. [all data]
Foner and Hudson, 1956
Foner, S.N.; Hudson, R.L.,
Ionization potential of the OH free radical by mass spectrometry,
J. Chem. Phys., 1956, 25, 602. [all data]
Katsumata and Lloyd, 1977
Katsumata, S.; Lloyd, D.R.,
The photoelectron spectra of the OH and OD radicals,
Chem. Phys. Lett., 1977, 45, 519. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
EA Electron affinity IE (evaluated) Recommended ionization energy 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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