hydrogen fluoride
- Formula: FH
- Molecular weight: 20.00634
- IUPAC Standard InChIKey: KRHYYFGTRYWZRS-UHFFFAOYSA-N
- CAS Registry Number: 7664-39-3
- Chemical structure:
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Ion clustering 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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: Br- + HF = (Br- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17.0 ± 2.0 | kcal/mol | Est | Larson and McMahon, 1984 | gas phase; Extrapolated from other bihalide data; B |
ΔrH° | 17.0 | kcal/mol | HPMS | Caldwell, Masucci, et al., 1989 | gas phase; M |
By formula: C3HF6O- + HF = (C3HF6O- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 25. | kcal/mol | ICR | Larson and McMahon, 1983 | gas phase; M |
By formula: C4F9O- + HF = (C4F9O- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17. | kcal/mol | ICR | Larson and McMahon, 1983 | gas phase; M |
By formula: C4H3F6O- + HF = (C4H3F6O- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 26. | kcal/mol | ICR | Larson and McMahon, 1983 | gas phase; M |
By formula: Cl- + HF = (Cl- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 21.8 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1984, 2 | gas phase; B,M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 22.5 | cal/mol*K | N/A | Larson and McMahon, 1984, 2 | gas phase; switching reaction(Cl-)SO2, Entropy change calculated or estimated; Larson and McMahon, 1984, 3; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 15.1 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1984, 2 | gas phase; B,M |
By formula: F- + HF = (F- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 45.8 ± 1.6 | kcal/mol | CIDC | Wenthold and Squires, 1995 | gas phase; B |
ΔrH° | 38.6 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1983 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B,M |
ΔrH° | >34.6 ± 4.6 | kcal/mol | Ther | Heni and Illenberger, 1985 | gas phase; From CHF=CHF. Outdataed HC2. thermo used. Current value ( Berkowitz, Ellison, et al., 1994) implies Haff>57.; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 21.9 | cal/mol*K | N/A | Larson and McMahon, 1983 | gas phase; switching reaction,Thermochemical ladder(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 32.0 ± 2.0 | kcal/mol | IMRE | Larson and McMahon, 1983 | gas phase; These relative affinities are ca. 10 kcal/mol weaker than threshold values (see Wenthold and Squires, 1995) for donors greater than ca. 27 kcal/mol in free energy. This discrepancy has not yet been resolved, though the stronger value appears preferable.; B |
Free energy of reaction
ΔrG° (kcal/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
32.0 | 289. | ICR | Larson and McMahon, 1983 | gas phase; switching reaction,Thermochemical ladder(F-)H2O, Entropy change calculated or estimated; Arshadi, Yamdagni, et al., 1970; M |
By formula: HF+ + HF = (HF+ • HF)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 33. | kcal/mol | PI | Tiedemann, Anderson, et al., 1979 | gas phase; ΔrH>; M |
By formula: H2F+ + HF = (H2F+ • HF)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 25.1 ± 2.5 | kcal/mol | PI | Tiedemann, Anderson, et al., 1979 | gas phase; M |
By formula: (H2F+ • HF) + HF = (H2F+ • 2HF)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 14.8 ± 4.2 | kcal/mol | PI | Tiedemann, Anderson, et al., 1979 | gas phase; M |
By formula: I- + HF = (I- • HF)
Bond type: Hydrogen bond (negative ion to hydride)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 15.0 ± 2.0 | kcal/mol | Est | Larson and McMahon, 1984 | gas phase; Extrapolated from other bihalide data; B |
ΔrH° | 15. | kcal/mol | PHPMS | Caldwell, Masucci, et al., 1989 | gas phase; M |
References
Go To: Top, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B.,
Gas phase bihalide and pseudohalide ions. An ICR determination of hydrogen bond energies in XHY- species (X,Y = F, Cl, Br, CN),
Inorg. Chem., 1984, 23, 2029. [all data]
Caldwell, Masucci, et al., 1989
Caldwell, G.W.; Masucci, J.A.; Ikonomou, M.G.,
Negative Ion Chemical Ionization Mass Spectrometry - Binding of Molecules to Bromide and Iodide Anions,
Org. Mass Spectrom., 1989, 24, 1, 8, https://doi.org/10.1002/oms.1210240103
. [all data]
Larson and McMahon, 1983
Larson, J.W.; McMahon, T.B.,
Strong hydrogen bonding in gas-phase anions. An ion cyclotron resonance determination of fluoride binding energetics to bronsted acids from gas-phase fluoride exchange equilibria measurements,
J. Am. Chem. Soc., 1983, 105, 2944. [all data]
Larson and McMahon, 1984, 2
Larson, J.W.; McMahon, T.B.,
Hydrogen bonding in gas phase anions. An experimental investigation of the interaction between chloride ion and bronsted acids from ICR chloride exchange equilibria,
J. Am. Chem. Soc., 1984, 106, 517. [all data]
Larson and McMahon, 1984, 3
Larson, J.W.; McMahon, T.B.,
Gas phase negative ion chemistry of alkylchloroformates,
Can. J. Chem., 1984, 62, 675. [all data]
Wenthold and Squires, 1995
Wenthold, P.G.; Squires, R.R.,
Bond dissociation energies of F2(-) and HF2(-). A gas-phase experimental and G2 theoretical study,
J. Phys. Chem., 1995, 99, 7, 2002, https://doi.org/10.1021/j100007a034
. [all data]
Heni and Illenberger, 1985
Heni, M.; Illenberger, E.,
The stability of the bifluoride ion (HF2-) in the gas phase,
J. Chem. Phys., 1985, 83, 6056. [all data]
Berkowitz, Ellison, et al., 1994
Berkowitz, J.; Ellison, G.B.; Gutman, D.,
Three methods to measure RH bond energies,
J. Phys. Chem., 1994, 98, 2744. [all data]
Arshadi, Yamdagni, et al., 1970
Arshadi, M.; Yamdagni, R.; Kebarle, P.,
Hydration of Halide Negative Ions in the Gas Phase. II. Comparison of Hydration Energies for the Alkali Positive and Halide Negative Ions,
J. Phys. Chem., 1970, 74, 7, 1475, https://doi.org/10.1021/j100702a014
. [all data]
Tiedemann, Anderson, et al., 1979
Tiedemann, P.W.; Anderson, S.L.; Ceyer, S.T.; Hirooka, T.; Ng, C.Y.; Mahan, B.H.; Lee, Y.T.,
Proton affinities of hydrogen halides determined by the molecular beam photoionization method,
J. Chem. Phys., 1979, 71, 605. [all data]
Notes
Go To: Top, Ion clustering data, References
- Symbols used in this document:
T Temperature ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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