Sulfur hexafluoride
- Formula: F6S
- Molecular weight: 146.055
- IUPAC Standard InChIKey: SFZCNBIFKDRMGX-UHFFFAOYSA-N
- CAS Registry Number: 2551-62-4
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Sulfur fluoride; OC-6-11; Elegas; SF6; Hexafluorure de soufre; UN 1080; Esaflon; sulphur hexafluoride
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Reaction thermochemistry data
Go To: Top, Henry's Law 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: 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
By formula: (F- • F6S) + F6S = (F- • 2F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 4.00 ± 0.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase; Entropy estimated. Gaff = +1.4 at 141 K |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | -1.40 ± 0.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase; Entropy estimated. Gaff = +1.4 at 141 K |
By formula: F6S- + F6S = (F6S- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 2.30 ± 0.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase; Entropy estimated. Gaff=+0.37 at 141K |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | -3.10 ± 0.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase; Entropy estimated. Gaff=+0.37 at 141K |
By formula: F- + F6S = (F- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 5.40 ± 0.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | -0.6 ± 3.0 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase |
By formula: C6H4N2O4- + F6S = (C6H4N2O4- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | <8.50 | kcal/mol | IMRB | Chowdhury and Kebarle, 1986 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | <1.90 | kcal/mol | IMRB | Chowdhury and Kebarle, 1986 | gas phase |
By formula: C6H4N2O4- + F6S = (C6H4N2O4- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | <8.40 | kcal/mol | IMRB | Chowdhury and Kebarle, 1986 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | <1.70 | kcal/mol | IMRB | Chowdhury and Kebarle, 1986 | gas phase |
By formula: F5S- + F6S = (F5S- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | <2.30 | kcal/mol | TDAs | Hiraoka, Shimizu, et al., 1995 | gas phase; No formation at 141 K |
By formula: Cl- + F6S = (Cl- • F6S)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrG° | <1.80 | kcal/mol | IMRB | Chowdhury and Kebarle, 1986 | gas phase |
Henry's Law data
Go To: Top, Reaction 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: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
k°H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference |
---|---|---|---|
0.00024 | 2400. | L | N/A |
Gas phase ion energetics data
Go To: Top, Reaction thermochemistry data, Henry's Law 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:
MM - Michael M. Meot-Ner (Mautner)
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
LL - Sharon G. Lias and Joel F. Liebman
B - John E. Bartmess
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 15.32 ± 0.02 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 137.5 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 131.6 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.910 ± 0.070 | N/A | Menk, Das, et al., 2014 | B |
1.030 ± 0.050 | N/A | Troe, Miller, et al., 2012 | W4 theory supports this (12KER/MAR) and lower level calculations have flaws; B |
1.070 ± 0.070 | TDAs | Chen, Wiley, et al., 1994 | B |
1.15 ± 0.15 | Kine | Chen, Shuie, et al., 1988 | From the temperature dependence of the API spectra of SF5-/SF6-; B |
1.05 ± 0.10 | TDEq | Grimsrud, Chowdhury, et al., 1985 | ΔGea(423 K) = -29.8 kcal/mol; ΔSea = +13 eu. See also Chowdhury, Heinis, et al., 1986, Bopp, Roscioli, et al., 2007; B |
1.39 ± 0.13 | Kine | Heneghan and Benson, 1983 | B |
0.799982 | Kine | Lifshitz, 1983 | Review: literature consistent with ΔS(act) for detachment = -14 eu; B |
1.20 ± 0.30 | N/A | Chase Jr., Curnutt, et al., 1982 | Literature average; B |
0.542052 | LPD | Drzaic and Brauman, 1982 | B |
>0.934931 | R-A | Refaey and Franklin, 1978 | B |
2.60 ± 0.10 | ECD | Chen and Chen, 2007 | B |
2.60 ± 0.10 | ECD | Chen and Chen, 2007 | B |
3.15999 | LPD | Datskos, Carter, et al., 1995 | Stated electron affinity is the Vertical Detachment Energy; B |
>0.698163 | ECD | Chen and Wentworth, 1983 | B |
0.46 ± 0.20 | NBIE | Compton, Reinhardt, et al., 1978 | B |
0.75 ± 0.10 | NBIE | Leffert, Tang, et al., 1974 | B |
0.54 ± 0.17 | NBIE | Compton and Cooper, 1973 | B |
0.53 ± 0.10 | NBIE | Compton, Cooper, et al., 1973 | B |
>0.60 ± 0.10 | Endo | Lifshitz, Tiernan, et al., 1973 | B |
0.95 ± 0.52 | IMRB | Fehsenfeld, 1971 | B |
0.43 | IMRB | Lifshitz, Hughes, et al., 1970 | B |
>0.698163 | ECD | Chen, George, et al., 1968 | B |
1.10002 | ES | Compton, Christophorou, et al., 1966 | B |
0.32 ± 0.15 | NBIE | Hubers and Los, 1975 | B |
1.49 ± 0.22 | SI | Kay and Page, 1964 | The Magnetron method, lacking mass analysis, is not considered reliable.; B |
Gas basicity at 298K
Gas basicity (review) (kcal/mol) | Reference | Comment |
---|---|---|
137.5 | Pepi, Ricci, et al., 2005 | T = 298K; PA(SF6) equated to PA(N2O) based on dissociative PT reactions with large entropy changes that may affect the kinetics.; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
15.30 | PE | Delwiche, 1969 | RDSH |
15.30 | PE | Delwiche, 1969 | RDSH |
15.35 ± 0.02 | PE | Frost, McDowell, et al., 1967 | RDSH |
15.7 | PE | Bieri, Asbrink, et al., 1982 | Vertical value; LBLHLM |
15.7 | PE | Sell and Kupperman, 1978 | Vertical value; LLK |
15.69 | PE | Potts, Lempka, et al., 1970 | Vertical value; RDSH |
15.81 | PE | Delwiche, 1969 | Vertical value; RDSH |
Appearance energy determinations
References
Go To: Top, Reaction thermochemistry data, Henry's Law 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.
Hiraoka, Shimizu, et al., 1995
Hiraoka, K.; Shimizu, A.; Minamitsu, A.; Nasu, M.; Fujimaki, S.; Yamabe, S.,
The small binding energies of the negative cluster ions: SF5-(SF6)1, SF6-(SF6)1 and F-(SF6)n (n=1 and 2), in the gas phase,
Chem. Phys. Lett., 1995, 241, 5-6, 623, https://doi.org/10.1016/0009-2614(95)00676-U
. [all data]
Chowdhury and Kebarle, 1986
Chowdhury, S.; Kebarle, P.,
Role of Binding Energies in A-.B and A.B- Complexes in the Kinetics of Gas Phase Electron Transfer Reactions:A- + B = A + B- Involving Perfluoro Compounds: SF6, C6F11CF3,
J. Chem. Phys., 1986, 85, 9, 4989, https://doi.org/10.1063/1.451687
. [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]
Menk, Das, et al., 2014
Menk, S.; Das, S.; Blaum, K.; Froese, M.W.; Lange, M.; Mukherjee, M.; Repnow, R.; Schwalm, D.; von Hahn, R.; Wolf, A.,
Vibrational autodetachment of sulfur hexafluoride anions at its long-lifetime limit,
Phys. Rev. A, 2014, 89, 2, 022502, https://doi.org/10.1103/PhysRevA.89.022502
. [all data]
Troe, Miller, et al., 2012
Troe, J.; Miller, T.M.; Viggiano, A.A.,
Communication: Revised electron affinity of SF6 from kinetic data,
J. Chem. Phys., 2012, 136, 12, 121102, https://doi.org/10.1063/1.3698170
. [all data]
Chen, Wiley, et al., 1994
Chen, E.C.M.; Wiley, J.R.; Batten, C.F.; Wentworth, W.E.,
Determination of the Electron Affinities of Molecules Using Negative Ion Mass Spectrometry,
J. Phys. Chem., 1994, 98, 1, 88, https://doi.org/10.1021/j100052a016
. [all data]
Chen, Shuie, et al., 1988
Chen, E.C.M.; Shuie, L.-R.; DSa, E.D.; Batten, C.F.; Wentworth, W.E.,
The Negative Ion States of SF6,
J. Chem. Phys., 1988, 88, 8, 4711, https://doi.org/10.1063/1.454710
. [all data]
Grimsrud, Chowdhury, et al., 1985
Grimsrud, E.P.; Chowdhury, S.; Kebarle, P.,
Electron affinity of SF6 and perfluoromethylcyclohexane. The unusual kinetics of electron transfer reactions A- + B- + A, where A = SF6 or perfluorinated cycloalkanes,
J. Chem. Phys., 1985, 83, 1059. [all data]
Chowdhury, Heinis, et al., 1986
Chowdhury, S.; Heinis, T.; Grimsrud, E.P.; Kebarle, P.,
Entropy Changes and Electron Affinities from Gas-Phase Electron Transfer Equilibria: A- + B = A + B-,
J. Phys. Chem., 1986, 90, 12, 2747, https://doi.org/10.1021/j100403a037
. [all data]
Bopp, Roscioli, et al., 2007
Bopp, J.C.; Roscioli, J.R.; Johnson, M.A.; Miller, T.M.; Viggiano, A.A.; Villano, S.M.; Wren, S.W.; Lineberger,
Spectroscopic characterization of the isolated SF6- and C4F8- anions: Observation of very long harmonic progressions in symmetric deformation modes upon photodetachment,
J. Phys. Chem. A, 2007, 111, 7, 1214-1221, https://doi.org/10.1021/jp0665372
. [all data]
Heneghan and Benson, 1983
Heneghan, S.P.; Benson, S.W.,
Kinetics and thermochemistry of electron attachment to SF6,
Int. J. Chem. Kinet., 1983, 15, 109. [all data]
Lifshitz, 1983
Lifshitz, C.,
Energy-entropy trade-offs in the unimolecular decompositions of SF6-,
J. Phys. Chem., 1983, 87, 3474. [all data]
Chase Jr., Curnutt, et al., 1982
Chase Jr.; Curnutt, J.L.; Downy Jr.; McDonald, R.A.; Syverrud, A.N.; Valenzuela, E.A.,
JANAF Thermochemical Tables 1982 Supplement,
J. Phys. Chem. Ref. Data, 1982, 11, 3, 695, https://doi.org/10.1063/1.555666
. [all data]
Drzaic and Brauman, 1982
Drzaic, P.S.; Brauman, J.I.,
Electron photodetachment of sulfur hexafluoride anion. Comments on the structure of SF6-,
J. Am. Chem. Soc., 1982, 104, 13. [all data]
Refaey and Franklin, 1978
Refaey, K.M.A.; Franklin, J.L.,
Collisonal decomposition of SF6-,
Int. J. Mass Spectrom. Ion Phys., 1978, 26, 125. [all data]
Chen and Chen, 2007
Chen, E.C.M.; Chen, E.S.,
Electron affinities and activation energies for reactions with thermal electrons: SF6 and SF5,
Phys. Rev. A, 2007, 76, 3, 032508, https://doi.org/10.1103/PhysRevA.76.032508
. [all data]
Datskos, Carter, et al., 1995
Datskos, P.G.; Carter, J.G.; Christophorou, L.G.,
Photodetachment of SF6-,
Chem. Phys. Lett., 1995, 239, 1-3, 38, https://doi.org/10.1016/0009-2614(95)00417-3
. [all data]
Chen and Wentworth, 1983
Chen, E.C.M.; Wentworth, W.E.,
Determination of molecular electron affinities using the electron capture detector in the pulse sampling mode at steady state,
J. Phys. Chem., 1983, 87, 45. [all data]
Compton, Reinhardt, et al., 1978
Compton, R.N.; Reinhardt, P.W.; Cooper, C.D.,
Collisional ionization between fast alkali atoms and selected hexafluoride molecules,
J. Chem. Phys., 1978, 68, 2023. [all data]
Leffert, Tang, et al., 1974
Leffert, C.B.; Tang, S.Y.; Rothe, E.W.; Cheng, T.C.,
Collisional ionization of Cs with SF6,
J. Chem. Phys., 1974, 61, 4929. [all data]
Compton and Cooper, 1973
Compton, R.N.; Cooper, C.D.,
Molecular electron affinities from collisional ionization of cesium. II. SF6 and TeF6,
J. Chem. Phys., 1973, 59, 4140. [all data]
Compton, Cooper, et al., 1973
Compton, R.N.; Cooper, R.D.; Divver, W.T.; Reinhardt, P.W.,
Molecular electron affinities from collisional ionization of cesium: SF6,
Bull. Am. Phys. Soc., 1973, 18, 810. [all data]
Lifshitz, Tiernan, et al., 1973
Lifshitz, C.; Tiernan, T.O.; Hughes, B.M.,
Electron affinities from endothermic negative-ion charge transfer reactions. IV. SF6, selected fluorocarbons, and other polyatomic molecules,
J. Chem. Phys., 1973, 59, 3182. [all data]
Fehsenfeld, 1971
Fehsenfeld, F.C.,
Ion Chemistry of SF6,
J. Chem. Phys., 1971, 54, 438. [all data]
Lifshitz, Hughes, et al., 1970
Lifshitz, C.; Hughes, B.M.; Tiernan, T.O.,
Electron Affinities for Endothermic Negative Ion Charge Transfer Reactions: NO2 and SF6,
Chem. Phys. Lett., 1970, 7, 4, 469, https://doi.org/10.1016/0009-2614(70)80339-6
. [all data]
Chen, George, et al., 1968
Chen, E.C.M.; George, R.D.; Wentworth, W.E.,
Experimental Determination of Rate Constants for Thermal Electron Attachment to Gaseous SF6 and C7F14,
J. Chem. Phys., 1968, 49, 4, 1973, https://doi.org/10.1063/1.1670342
. [all data]
Compton, Christophorou, et al., 1966
Compton, R.N.; Christophorou, L.G.; Hurst, G.S.; Reinhardt, P.W.,
Nondissociative Electron Capture in Complex Molecules and Negative Ion Lifetimes,
J. Chem. Phys., 1966, 45, 12, 4634, https://doi.org/10.1063/1.1727547
. [all data]
Hubers and Los, 1975
Hubers, M.M.; Los, J.,
Ion pair formation in alkali-SF6 collisions: Dependence on collisional and vibrational energy,
Chem. Phys., 1975, 10, 235. [all data]
Kay and Page, 1964
Kay, J.; Page, F.M.,
Determination of Electron Affinities. Part 7.- Sulphur Hexafluoride and Disulphur Decafluoride,
Trans. Farad. Soc., 1964, 60, 1042, https://doi.org/10.1039/tf9646001042
. [all data]
Pepi, Ricci, et al., 2005
Pepi, F.; Ricci, A.; Di Stefano, M.; Rosi, M.,
Gas phase protonation of trifluoromethyl sulfur pentafluoride,
Phys. Chem. Chem. Phys., 2005, 7, 1181. [all data]
Delwiche, 1969
Delwiche, J.,
Ionization of sulphur hexafluoride by photon and electron impact,
Bull. Classe Sci. Acad. Roy. Belg., 1969, 55, 215. [all data]
Frost, McDowell, et al., 1967
Frost, D.C.; McDowell, C.A.; Sandhu, J.S.; Vroom, D.A.,
Photoelectron spectrum of sulfur hexafluoride at 584 A,
J. Chem. Phys., 1967, 46, 2008. [all data]
Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W.,
30.4-nm He(II) photoelectron spectra of organic molecules,
J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]
Sell and Kupperman, 1978
Sell, J.A.; Kupperman, A.,
Angular distributions in the photoelectron spectroscopy of SF6,
Chem. Phys., 1978, 33, 379. [all data]
Potts, Lempka, et al., 1970
Potts, A.W.; Lempka, H.J.; Streets, D.G.; Price, W.C.,
Photoelectron spectra of the halides of elements in groups III, IV, V and VI,
Phil. Trans. Roy. Soc. (London), 1970, A268, 59. [all data]
Pullen and Stockdale, 1976
Pullen, B.P.; Stockdale, J.A.D.,
Dissociative ionization of SF6 by electron impact,
Int. J. Mass Spectrom. Ion Phys., 1976, 19, 35. [all data]
Hildenbrand, 1973
Hildenbrand, D.L.,
Mass spectrometric studies of some gaseous sulfur fluorides,
J. Phys. Chem., 1973, 77, 897. [all data]
Mitsuke, Suzuki, et al., 1990
Mitsuke, K.; Suzuki, S.; Imamura, T.; Koyano, I.,
Negative-ion mass spectrometric study of ion-pair formation in the vacuum ultraviolet. III. SF6 Ü F- + SF5+,
J. Chem. Phys., 1990, 93, 8717. [all data]
Sasanuma, Ishiguro, et al., 1979
Sasanuma, M.; Ishiguro, E.; Hayaisha, T.; Masuko, H.; Morioka, Y.; Nakajima, T.; Nakamura, M.,
Photoionisation of SF6 in the XUV region,
J. Phys. B:, 1979, 12, 4057. [all data]
Stone and Wytenberg, 1989
Stone, J.A.; Wytenberg, W.J.,
A high pressure mass spectrometric study of the formation and chemistry of the pentafluorosulphur cation (SF5+),
Int. J. Mass Spectrom. Ion Processes, 1989, 94, 269. [all data]
Tichy, Javahery, et al., 1987
Tichy, M.; Javahery, G.; Twiddy, N.D.; Ferguson, E.E.,
The thermal energy reactions HCl+ + SF6 Ü SF5+ + HF + Cl and HCl+ + CF4 Ü CF3+ + HF + Cl,
Int. J. Mass Spectrom. Ion Processes, 1987, 79, 231. [all data]
Shul, Upschulte, et al., 1987
Shul, R.J.; Upschulte, B.L.; Passarella, R.; Keesee, R.G.; Castleman, A.W.,
Thermal energy charge-transfer reactions of Ar+ and Ar2+,
J. Phys. Chem., 1987, 91, 2556. [all data]
Babcock and Streit, 1981
Babcock, L.M.; Streit, G.E.,
Ion-molecule reactions of SF6: Determination of I. P. (SF6), A. P.(SF5+/SF6), and D(SF5-F),
J. Chem. Phys., 1981, 74, 5700. [all data]
Simm, Danby, et al., 1975
Simm, I.G.; Danby, C.J.; Eland, J.H.D.; Mansell, P.I.,
Translational energy release in the loss of fluorine atoms from the ions SF6+, CF4+ and C2F6+,
J. Chem. Soc., 1975, 426. [all data]
Dibeler and Walker, 1966
Dibeler, V.H.; Walker, J.A.,
Photoionization efficiency curve for SF6 in the wavelength region 1050 to 600,
J. Chem. Phys., 1966, 44, 4405. [all data]
Fox and Curran, 1961
Fox, R.E.; Curran, R.K.,
Ionization processes in CCl4 and SF6 by electron beams,
J. Chem. Phys., 1961, 34, 1595. [all data]
Dibeler and Mohler, 1948
Dibeler, V.H.; Mohler, F.L.,
Dissociation of SF6, CF4, and SiF4 by electron impact,
J. Res. Natl. Bur. Stand. U.S., 1948, 40, 25. [all data]
Notes
Go To: Top, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity IE (evaluated) Recommended ionization energy d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K 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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