hydrogen fluoride
- Formula: FH
- Molecular weight: 20.00634
- IUPAC Standard InChIKey: KRHYYFGTRYWZRS-UHFFFAOYSA-N
- CAS Registry Number: 7664-39-3
- 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 ion energetics data
Go To: Top, Ion clustering 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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LL - Sharon G. Lias and Joel F. Liebman
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 16.03 ± 0.04 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 116. | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 109.2 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
16.06 | PE | Bieri, Schmelzer, et al., 1980 | LLK |
15.98 ± 0.04 | PI | Tiedemann, Anderson, et al., 1979 | LLK |
16.05 | EI | Foner and Hudson, 1978 | LLK |
15.98 ± 0.04 | PI | Ng, Trevor, et al., 1977 | LLK |
16. ± 1. | EI | Farber and Srivastava, 1977 | LLK |
16.039 | TE | Guyon, Spohr, et al., 1976 | LLK |
16.05 ± 0.04 | AUG | Shaw and Thomas, 1975 | LLK |
16.1 | PE | Debies and Rabalais, 1975 | LLK |
16.044 ± 0.003 | PE | Walker, Dehmer, et al., 1973 | LLK |
16.03 ± 0.01 | PE | Berkowitz, 1971 | LLK |
16.007 ± 0.010 | PI | Berkowitz, Chupka, et al., 1971 | LLK |
16.05 ± 0.01 | PE | Brundle, 1970 | RDSH |
15.92 ± 0.01 | PI | Dibeler, Walker, et al., 1969 | RDSH |
16.05 ± 0.01 | PE | Lempka, Passmore, et al., 1968 | RDSH |
16.06 ± 0.01 | PE | Frost, McDowell, et al., 1967 | RDSH |
16.12 ± 0.04 | PE | Banna and Shirley, 1975 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
H+ | 19.42 ± 0.01 | F | PI | Berkowitz, Ellison, et al., 1994 | LL |
H+ | 19.444 | F | PI | Berkowitz and Wahl, 1973 | LLK |
H+ | 16.061 ± 0.005 | F- | PI | Berkowitz, Chupka, et al., 1971 | LLK |
H+ | 19.45 ± 0.01 | F | PI | Berkowitz, Chupka, et al., 1971, 2 | LLK |
H+ | >19.44 ± 0.02 | F | PE | Brundle, 1970 | RDSH |
De-protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 372. ± 1. | kcal/mol | AVG | N/A | Average of 6 out of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 365.67 ± 0.18 | kcal/mol | H-TS | Blondel, Delsart, et al., 2001 | gas phase; Given: 3.4011895(25) eV, or 27432.446(19) cm-1, or 78.433266(577) kcal/mol; B |
ΔrG° | 365.53 | kcal/mol | H-TS | Martin and Hepburn, 2000 | gas phase; Given: 371.334±0.003 kcal/mol (corr to 298K with data from Wagman, Evans, et al., 1982).H(0K)=370.422±0.003; B |
ΔrG° | 365.67 ± 0.18 | kcal/mol | H-TS | Blondel, Cacciani, et al., 1989 | gas phase; Reported: 3.401190±0.000004 eV. acidity includes 0.9 kcal 0 to 298 K correction.; B |
ΔrG° | 365.5 ± 2.0 | kcal/mol | IMRE | Bierbaum, Schmidt, et al., 1981 | gas phase; B |
ΔrG° | 359.40 | kcal/mol | N/A | Check, Faust, et al., 2001 | gas phase; FeCl3-; ; ΔS(EA)=5.0; B |
Ion clustering 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 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, Gas phase ion energetics data, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Bieri, Schmelzer, et al., 1980
Bieri, G.; Schmelzer, A.; Asbrink, L.; Jonsson, M.,
Fluorine and the fluoroderivatives of acetylene and diacetylene studied by 30.4 nm He(II) photoelectron spectroscopy,
Chem. Phys., 1980, 49, 213. [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]
Foner and Hudson, 1978
Foner, S.N.; Hudson, R.L.,
Mass spectrometry of excited state molecules: Observation of highly vibrationally excited HF by ionization potential measurement,
J. Chem. Phys., 1978, 68, 2987. [all data]
Ng, Trevor, et al., 1977
Ng, C.Y.; Trevor, D.J.; Tiedemann, P.W.; Ceyer, S.T.; Kronebusch, P.L.; Mahan, B.H.; Lee, Y.T.,
Photoionization of dimeric polyatomic molecules: proton affinities of H2O and HF,
J. Chem. Phys., 1977, 67, 4235. [all data]
Farber and Srivastava, 1977
Farber, M.; Srivastava, R.D.,
Mass spectrometric determination of the heats of formation of the silane fluorides,
Chem. Phys. Lett., 1977, 51, 307. [all data]
Guyon, Spohr, et al., 1976
Guyon, P.-M.; Spohr, R.; Chupka, W.A.; Berkowitz, J.,
Threshold photoelectron spectra of HF, DF, F2,
J. Chem. Phys., 1976, 65, 1650. [all data]
Shaw and Thomas, 1975
Shaw, R.W., Jr.; Thomas, T.D.,
Auger electron spectrum and ionization potentials of the HF molecule,
Phys. Rev. A:, 1975, 11, 1491. [all data]
Debies and Rabalais, 1975
Debies, T.P.; Rabalais, J.W.,
Calculated photoionization cross-sections and angular distributions for the isoelectronic series Ne, HF, H2O, NH3, and CH4,
J. Am. Chem. Soc., 1975, 97, 487. [all data]
Walker, Dehmer, et al., 1973
Walker, T.E.H.; Dehmer, P.M.; Berkowitz, J.,
Rotational band shapes in photoelectron spectroscopy: HF DF,
J. Chem. Phys., 1973, 59, 4292. [all data]
Berkowitz, 1971
Berkowitz, J.,
Experimental potential energy curves for X2{PI} and 2Σ+ states of HF+,
Chem. Phys. Lett., 1971, 11, 21. [all data]
Berkowitz, Chupka, et al., 1971
Berkowitz, J.; Chupka, W.A.; Guyon, P.M.; Holloway, J.H.; Spohr, R.,
Photoionization mass spectrometric study of F2, HF, and DF,
J. Chem. Phys., 1971, 54, 5165. [all data]
Brundle, 1970
Brundle, C.R.,
Ionization and dissociation energies of HF and DF and their bearing on D(F2),
Chem. Phys. Lett., 1970, 7, 317. [all data]
Dibeler, Walker, et al., 1969
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E.,
Photoionization study of the dissociation energy of fluorine and the heat of formation of hydrogen fluoride,
J. Chem. Phys., 1969, 51, 4230. [all data]
Lempka, Passmore, et al., 1968
Lempka, H.J.; Passmore, T.R.; Price, W.C.,
The photoelectron spectra and ionized states of the halogen acids,
Proc. Roy. Soc. (London), 1968, A304, 53. [all data]
Frost, McDowell, et al., 1967
Frost, D.C.; McDowell, C.A.; Vroom, D.A.,
Photoelectron spectra of the halogens and the hydrogen halides,
J. Chem. Phys., 1967, 46, 4255. [all data]
Banna and Shirley, 1975
Banna, M.S.; Shirley, D.A.,
Molecular photoelectron spectroscopy at 132.3 eV. The second-row hydrides,
J. Chem. Phys., 1975, 63, 4759. [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]
Berkowitz and Wahl, 1973
Berkowitz, J.; Wahl, A.C.,
The dissociation energy of fluorine,
Adv. Fluorine Chem., 1973, 7, 147. [all data]
Berkowitz, Chupka, et al., 1971, 2
Berkowitz, J.; Chupka, W.A.; Guyon, P.M.; Holloway, J.; Spohr, R.,
Photo-ionization studies of F2, HF, DF, and the xenon fluorides,
Advan. Mass Spectrom., 1971, 5, 112. [all data]
Blondel, Delsart, et al., 2001
Blondel, C.; Delsart, C.; Goldfarb, F.,
Electron spectrometry at the mu eV level and the electron affinities of Si and F,
J. Phys. B: Atom. Mol. Opt. Phys., 2001, 34, 9, L281-L288, https://doi.org/10.1088/0953-4075/34/9/101
. [all data]
Martin and Hepburn, 2000
Martin, J.D.D.; Hepburn, J.W.,
Faraday Disc. Chem. Soc., 2000, 115, 416. [all data]
Wagman, Evans, et al., 1982
Wagman, D.D.; Evans, W.H.; Parker, V.B.; Schumm, R.H.; Halow, I.; Bailey, S.M.; Churney, K.L.; Nuttall, R.L.,
The NBS Tables of Chemical Thermodynamic Properties (NBS Tech Note 270),
J. Phys. Chem. Ref. Data, Supl. 1, 1982, 11. [all data]
Blondel, Cacciani, et al., 1989
Blondel, C.; Cacciani, P.; Delsart, C.; Trainham, R.,
High Resolution Determination of the Electron Affinity of Fluorine and Bromine using Crossed Ion and Laser Beams,
Phys. Rev. A, 1989, 40, 7, 3698, https://doi.org/10.1103/PhysRevA.40.3698
. [all data]
Bierbaum, Schmidt, et al., 1981
Bierbaum, V.M.; Schmidt, R.J.; DePuy, C.H.; Mead, R.H.; Schulz, P.A.; Lineberger, W.C.,
Reactions of carbanions with triplet and singlet molecular oxygen,
J. Am. Chem. Soc., 1981, 103, 6262. [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]
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]
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]
Notes
Go To: Top, Gas phase ion energetics data, Ion clustering data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy 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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